Methodology
How RentSift builds reports
RentSift starts with federal, state, and local government records, then supplements them with clearly labeled licensed and open-data sources where public records do not answer the renter's question. Here is how each signal category works.
Crime incident data is sourced from local law enforcement agencies and government open data portals. Reports show the source window on the police row: most feeds use the last 12 months, while Fairfax County uses the current Fairfax Police weekly CSV when it has newer nearby records than the FCPOD layers. When the feed exposes block text, reports use matching public block labels first; otherwise they summarize the report mix inside published-coordinate distance bands. Nearby-area context stays separate from claims about the building itself.
Code enforcement and 311 data from government portals. Where we have coordinates, we split requests within ~150 ft of the geocoded pin (a close-proximity band that can include an adjacent property, not an address match) from the rest of the nearby radius. Fairfax PLUS matches the searched street address. Pest, noise, trash, and housing-maintenance categories are labeled where available.
When configured, Walk Score® (Walk Score API) supplies walk, transit, and bike scores. If the API is unavailable, we may fall back to OpenStreetMap-based transit density and similar signals only.
Residential electricity and natural gas budget ranges start with U.S. Energy Information Administration (EIA) monthly state residential rates, then add U.S. Census Bureau American Community Survey (ACS) utility-cost and inclusion context where available. Provider options are separate service-area context from official utility or local-government sources and must be verified for the exact address.
Building details, listed owner names, sale history, and property tax values come from official county or city property records where available. RentSift keeps these tied to the searched address and separates them from management-company or lease records.
Named parks prefer live official local-government GIS layers in DC, Montgomery, Prince George's, Fairfax County, Arlington, Alexandria, Loudoun, and Prince William County. Independent cities without a configured official layer use a labeled OpenStreetMap-derived fallback through Geoapify or Overpass; OpenStreetMap also supplements categories such as dog parks and playgrounds. Grocery, convenience, pharmacy, and gym access remains OpenStreetMap-derived. Reports identify the source actually used.
Automated aggregate registered sex offender counts within defined radii are currently available for Washington, DC. Maryland and Virginia reports do not show automated counts or registry links yet; renters can run a manual address check on the official Maryland and Virginia state registries. RentSift displays no names or personal information.
Additional sources on reports
Beyond the core public-record categories above, individual report sections may include:
- HUD Small Area Fair Market Rents (SAFMR): U.S. Department of Housing and Urban Development, HUD User FMR datasets. Under 24 CFR § 888.113, FMR is a gross-rent benchmark built around the 40th percentile and includes tenant-paid utilities other than telephone. Report SAFMR dollars apply that benchmark at ZIP level. RentSift does not calculate a deal percentage against an advertised listing price because the two measures are not gross-to-gross.
- Housing-program utility allowances: Current official one-bedroom component schedules from the DC Housing Authority and Loudoun County HCV program. These schedules appear only when a matching assisted-housing property record supports applying the program context to the searched address. They are administrative planning allowances for tenant-furnished services, not predicted household bills. Reports show components rather than summing every line and stop rendering a schedule after its annual review date unless the source is refreshed.
- Flood hazard: FEMA National Flood Hazard Layer via the FEMA Flood Map Service Center.
- Eviction filing statistics: DC reports use the DC Office of the Tenant Advocate monthly eviction data; Maryland reports use the Maryland Judiciary District Court eviction case dataset; Virginia reports use LSC Civil Court Data. RentSift does not fall back to the retired Princeton tract snapshot; when an active court source is unavailable, the report shows the source as unavailable instead of substituting historical data.
- Neighborhood demographics and commute: U.S. Census Bureau American Community Survey (ACS). Census API requests carry the required API key when configured; if that endpoint rejects or cannot serve a report request, RentSift uses Census Reporter's mirror of the same current ACS 5-year tables rather than silently dropping the card. Address reports retain race/ethnicity and sex and display the published 90% margins of error for every rendered demographic estimate that has one. County unemployment may include BLS Local Area Unemployment Statistics (LAUS). The Trend Map's Income, Median age, and Education layers use the same ACS 5-year estimates at ZIP level, shown in quantile bins with margins of error; the Education layer is the share of adults 25 and older with a bachelor's degree or higher (ACS table B15003).
- Schools: proficiency and relative standing come from state report-card sources: Maryland Report Card, Virginia School Quality Profiles, and DC School Report Card. Assigned schools use district boundary services where integrated: DCPS EBIS, MCPS, PGCPS School Finder, FCPS Boundary Locator, Loudoun County Public Schools, and Arlington Public Schools. NCES CCD/EDGE is used only for nearby school context or fallback directory/location data, not as the preferred assigned-school authority.
- Management company complaints: Consumer Financial Protection Bureau Consumer Complaint Database (aggregate counts and links only).
- Neighborhood map (satellite): Esri World Imagery tiles; attribution is shown on the map control (Esri, Maxar, Earthstar Geographics, and OpenStreetMap contributors as applicable).
- Affordable housing: Public property-based program records from HUD LIHTC, HUD Project-Based Section 8 / Multifamily Assistance, Montgomery County MPDU rentals, DC Open Data Affordable Housing, Prince George's County DHCD, Fairfax County ADU/WDU, Arlington MHUD, and Loudoun ADU/UHNU materials. The affordable-apartment page and individual reports use loaded public property-based records; “No public program record found” is not a claim about tenant-based vouchers, unpublished units, expired records, or leasing-office policy.
- Transit proximity: Nearest Metro stations and bus stops from the WMATA Developer API where WMATA serves the searched area. For the nearest WMATA bus stop, typical weekday headways are calculated from WMATA's official static GTFS (the schedule feed that supports its trip planner) for the displayed service date. The publisher refreshes that feed weekly; runtime refuses the snapshot after 14 days or its published service-calendar end. If the live WMATA nearby-stop or station lookup fails, that same current snapshot can supply address-nearby scheduled Metrobus stops and active routes; the report marks the result partial, says the live lookup is unavailable, and withholds Metro-station context rather than treating the schedule as live data. No fallback is used after the snapshot expires. Prince George's County TheBus routes and headways use its current published GTFS with the same age-and-calendar rule. Schedule-derived headways are not live-arrival predictions.
- Internet options: RentSift does not currently make an automated per-address provider claim. The former third-party BroadbandMap alpha integration was retired after it became key-gated, and the FCC's licensed per-location data is not available through a free, terms-compliant address API. Reports link renters to the FCC National Broadband Map for a self-serve address lookup, then ask renters to confirm unit wiring, actual performance, building bulk internet, installation timing, and plan price with the leasing office and provider.
- Starting price vs nearby: A scheduled weekly browser collection records the lowest published listing price shown for each unit size on public rental-listing browse pages. RentSift compares a matched building's entry price with the median across tracked buildings' entry prices for the same unit type and ZIP. This is not an average of available units, a signed-lease dataset, a representative rent roll, or necessarily base rent. Historical snapshots did not preserve whether a source called the amount base rent or total monthly price; the report labels that price type unknown and does not combine it with modeled fee ranges. This is RentSift market context only; it is separate from HUD Fair Market Rent and separate from the ZORI trend map.
- Rental licensing (Montgomery County): License status from MoCo Housing Licensing & Registration.
- Lead disclosure: Based on the building's original year built in government property records. EPA / HUD disclosure rules apply to most pre-1978 housing; reports flag those buildings and explain when a later update year likely means remodel or tax-record updates rather than original construction.
- Smoking policy: Montgomery County Board of Health Regulation 17-210 and County Code §24-9 prohibit smoking in indoor common areas of multi-unit residential buildings. Maryland's statewide Clean Indoor Air Act covers indoor public spaces and workplaces but is not presented as a blanket private-apartment common-area rule. Virginia bans smoking in elevators but has no blanket rule for every apartment common area. DC has no blanket citywide ban covering every common area of a private apartment building; other workplace or public-place rules may apply. Its 2019 apartment-common-area measure was never funded and was repealed in 2021.
- Owner, sale, and building records: Official property-record sources: DC CAMA / Owner Polygons, Maryland SDAT, Fairfax County Tax Administration ArcGIS, Arlington County DataHub, and Loudoun County GeoHub. Listed owners are shown only where the official source provides them; sales and property tax values stay in the property section, not the landlord-management section.
- Construction activity (Fairfax County): Building permits and active construction from Fairfax County DevelopmentTracker.
- Housing inspection violations (PG County): The former PG County Open Data dataset is marked archival and has no current public successor in the county's inventory. RentSift reports this check as unavailable instead of treating the absence of recent rows as a clean inspection history.
How to read report signals
RentSift is designed to show source-labeled records and renter questions, not a proprietary safety verdict. Some sections may include source-specific metrics, such as Walk Score, school assessment context, HUD REAC scores, or count-based summaries. Those metrics are supporting context, not a certification that a building or neighborhood is good, bad, safe, or unsafe.
| Category | Scope | What it measures |
|---|---|---|
| Nearby public records | Optional / nearby | Reported incidents and public records near the searched pin. Public block-label matches use the source's block text; distance-band rows use published map coordinates when no block-label match is available. Both are nearby context, not exact-building evidence or a safety score. |
| Code & complaints | Property / nearby | 311 complaints, code violations, and housing inspections split by address match or nearby context where possible |
| Walkability | Area | Walk Score, transit access, bike context, and nearby destinations where available |
| Schools | Assigned / nearby | Assigned district schools, current state assessment context within each school's own state system, and nearby school directory context where available |
| Utilities | Area / provider | Source-backed utility budget ranges and provider context where public data supports it |
| Internet options | Self-serve | No automated provider claim. Use the linked FCC National Broadband Map for the exact address, then confirm in-unit wiring, installability, performance, bulk-building rules, and price |
| Starting price vs nearby | ZIP / property | A building's lowest published listing price for a unit type compared with the median across tracked buildings' entry prices in its ZIP; not an average of available units, signed rent, or necessarily base rent, and separate from HUD FMR and the ZORI map |
| Fees and move-in context | Property / effective jurisdiction | The report shows required-fee, optional-fee, and move-in planning components under the effective jurisdiction's rules. Historical listing prices with unknown semantics are never added to those ranges. A combined model can return only when the same snapshot explicitly identifies base rent or total monthly price; total-monthly-price rows never add required fees again. Montgomery County regulated-unit narrowing is used only when government year-built and licensing fields clear the initial coverage screen, and all other exemptions still require verification. |
| Next checks | Hero action summary | A short list inside the report hero for items that need confirmation or review before applying. Clear or strong sections stay in their supporting report areas. It is not legal advice, a safety rating, or a guarantee of current conditions. |
| Neighborhood | Area | Census and local context such as demographics, commute, and public-record coverage limits |
| Grocery access | Nearby | Grocery stores, pharmacies, convenience stores, parks, and gyms near the address |
| Lease questions | Action | Practical questions generated from the records shown in the report |
If a data source is unavailable or returns no results, that signal is marked as missing, unavailable, or no matching record rather than treated as proof that no issue exists.
Findings closer to the searched address are prioritized in the report, but nearby public records remain context only unless the source supports an address-level match.
Data freshness
Reports and map pages are generated from a mix of live API calls and refreshed local public-data extracts. Data freshness depends on how frequently each source agency updates their datasets and how often the extract can be refreshed (typically daily or weekly for crime and complaint data where available, and monthly for utility rate and ZORI rent-index information; the Trend Map's Income, Median age, and Education layers use Census ACS 5-year estimates, refreshed with each annual ACS release). Fairfax County police context uses the latest downloaded weekly CSV when it is fresher than the FCPOD ArcGIS crime layers, and the report labels that shorter window directly.
Reports are cached for a limited period to reduce load on source APIs. The cache status is displayed on each report.
Important disclaimer
RentSift reports are provided for informational purposes only and do not constitute real estate, financial, legal, or investment advice. Data is sourced from publicly available government databases and third-party providers. We do not guarantee the accuracy, completeness, or timeliness of any information presented.
Users should independently verify all information before making rental or housing decisions. RentSift shall not be liable for any direct, indirect, incidental, or consequential damages arising from use of this information.
This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau. Geographic data includes information from OpenStreetMap contributors, available under the Open Database License.
Walk Score®: When displayed, walk, transit, and bike scores are provided by Walk Score (Smarter Travel Media LLC) under their API terms. Walk Score is a registered trademark of Smarter Travel Media LLC.
Local parks GIS / Geoapify / OpenStreetMap: Named parks use a live official local-government GIS layer where configured. Grocery, pharmacy, gym, supplemental park amenities, and jurisdictions without a queryable official layer use the Geoapify Places API, which uses OpenStreetMap data, or Overpass / OpenStreetMap fallback where Geoapify is unavailable. The report labels which source supplied its named parks. Geoapify is not affiliated with RentSift.
HUD, FEMA, and eviction sources: Fair market rent figures cite HUD SAFMR; flood zones cite FEMA; eviction statistics cite their active public source in the report: DC OTA, Maryland Judiciary, or LSC Civil Court Data. Historical Princeton tract data is retired and is not used as a fallback. These agencies are not affiliated with RentSift.
Metrics, counts, and projections reflect data available at the time of report generation and may not reflect current conditions. Utility cost projections are estimates based on state-level average rates and explicit modeled usage anchors; the usage values are not represented as measured state averages and will vary by household. Separately labeled housing-program utility allowances are administrative schedule components, not expected bills, and must be selected according to the actual building, fuel, appliances, and tenant-paid services.
School proficiency data is sourced from official state Department of Education publications: Virginia Standards of Learning (SOL) pass rates from schoolquality.virginia.gov, DC OSSE School Report Card Assessment scores from osse.dc.gov, and Maryland MCAP ELA & Math proficiency rates from reportcard.msde.maryland.gov. All data reflects the 2024-2025 school year. Proficiency metrics vary by state and are not directly comparable across state lines. Assigned-school boundaries come from district boundary services where available, including DCPS EBIS, MCPS attendance zones, FCPS Boundary Locator, Arlington Public Schools boundaries, and Loudoun County Public Schools zones. NCES CCD/EDGE public school locations are used only for nearby context or fallback, not as the source of assigned schools.
Tenant rights information, including rent stabilization caps, renewal policies, application-fee caps, security-deposit limits, late-fee limits, and cost guardrails, is sourced from official government websites and Census incorporated-place geography where city boundaries affect the rule set. Current cost sources include DC OTA/Rental Housing Commission, DC Code, Montgomery County DHCA, Prince George's County PRSA policy, Takoma Park, Rockville, Gaithersburg, Mount Rainier, Maryland Real Property law, and the Virginia Residential Landlord and Tenant Act for Fairfax County, Arlington, Loudoun County, and statewide legal-baseline context for Virginia reports that resolve outside those three proof markets, such as Alexandria, Falls Church, or Fairfax City. Guardrails do not replace a building's lease, application packet, or written fee schedule. Laws and regulations change frequently. RentSift does not provide legal advice. Consult an attorney or your local tenant rights office for guidance on your specific situation.
A note on 311 complaint data: 311 complaint counts reflect what residents have reported, not necessarily the full extent of conditions at a location. Research has shown that 311 reporting rates vary by neighborhood, with some areas systematically underreporting issues. An address with zero complaints does not guarantee the absence of problems, particularly in areas with lower reporting rates. We present complaint data as one signal among many, not as a definitive assessment of building conditions.
Environmental compliance data is sourced from the EPA Enforcement and Compliance History Online (ECHO) database, which tracks facilities regulated under the Clean Air Act, Clean Water Act, and Resource Conservation and Recovery Act.