Data coverage
Data coverage
Section titled “Data coverage”This is the public version of the internal coverage register kept during the 2026-07 audit. The rule behind every row: a gap gets disclosed, not hidden, and a missing signal is labeled “not tracked” — never silently rendered as zero, which would read as “nothing is wrong here” instead of “we never looked.” Per-feed cadence and vintage: data sources. What a null does to a score: limitations.
Valuation coverage by county
Section titled “Valuation coverage by county”| County | Property types modeled | ARV / as-is | Tax estimate | Confidence |
|---|---|---|---|---|
| Cook | SFH and 2–4 unit (mf2_4) |
Full comp-based valuation — live comps or neighborhood premium, gated | Cook Clerk effective rates (2023) | Standard — see accuracy by segment |
| Lake | SFH (limited evidence) | Partial — renovated-value estimates draw on Lake County GIS sale records where ≥4 qualifying nearby sales exist (method “Lake County sales evidence (limited)”); otherwise as-is only or honestly suppressed (tract_not_ingested) |
County-median rate estimate only | Capped at 45 — single-source county evidence, disclosed on every response |
Condos and townhomes are not modeled in either county. The engine’s property types are sfh
and mf2_4 only. A condo or townhome address returns a search result and tract context, never a
silent ARV — searches and valuation responses say so explicitly rather than guessing at a number
for a property type the model has never been graded against.
Chicago-only signals
Section titled “Chicago-only signals”These feeds come from the Chicago Data Portal and don’t exist for any other municipality. Outside city limits they are not tracked — the field is null, not zero, because absence of data is not the same claim as absence of risk.
| Signal | Coverage | Outside Chicago |
|---|---|---|
| Building permits (renovation + business momentum, 18 mo) | Chicago only | Not tracked |
| 311 categories, incl. basement-flood calls | Chicago only | Not tracked |
| Commercial permits and new licenses | Chicago only | Not tracked |
| Governance burden (point-of-sale inspection friction, municipal fiscal distress proxies) | Chicago only | Not tracked |
Suburban Cook and all of Lake County fall back to the county-wide feeds only — HMDA, Census, property tax, and FEMA flood — for every signal in this table. That is a coverage ceiling of the source data, not a bug in the model; risk score and BRRRR/flip scores document exactly which of their factors this affects.
Listings coverage
Section titled “Listings coverage”Public-beta active inventory is served only from licensed sources. Today that means RentCast in the configured Cook and Lake search areas; the MRED/RESO adapter remains disabled until the operator’s agreement permits display. Legacy Redfin/Zillow scrape lanes fail closed and are not served unless an explicit internal-only override is set.
RentCast surfaces additional property types, including some condos and townhomes. Unsupported types are visible but unscored: listing facts may appear, but ARV, deal score and investor target price remain withheld until the valuation model supports that type. Licensed does not mean complete MLS coverage; missing inventory is an expected beta limitation.
Vintages
Section titled “Vintages”Every tract-level field carries its own as_of date; these are the vintages behind the numbers
as of this page’s last edit.
| Field | Vintage |
|---|---|
| Tract signals (all 26 metrics) | Rebuilt monthly; dated per field |
| Cook property tax rates | 2023 |
| HMDA mortgage volume / loan size / FHA share | 2024 |
| Restricted offline income and crime diagnostics | Withheld from public payloads, scores, risk, and lenses |
| Market temperature (sale-to-list, days-on-market) | 2026-03 |
| ZHVI / ZORI (Zillow prices and rents) | 2026-04 |
| SAFMR (HUD rent anchor) | FY2026 |
Rent evidence
Section titled “Rent evidence”Zillow’s ZORI covers roughly 288 Illinois ZIP codes. Inside that footprint, the rent anchor blends SAFMR and ZORI; outside it, the anchor is SAFMR alone, bounded 0.7–1.6× the SAFMR-implied figure so a thin-data ZIP can’t produce a fantasy rent in either direction. Detail: rent model.
Restricted diagnostics and jobs
Section titled “Restricted diagnostics and jobs”Crime and income-derived diagnostics are retained only in offline pipeline assets for fairness and data-quality review. They are stripped from public tract payloads and do not affect public scores, property risk, recommendations, or lenses (see fair housing). Job growth is Census LODES 2022, the latest vintage published, Cook + Lake.
What’s coming
Section titled “What’s coming”Two changes close the biggest gaps on this page: wiring the Lake County sales corpus into the valuation waterfall (unlocks real ARV and as-is values for Lake, not just tract context), and adding a licensed MLS feed once the MRED/RESO agreement is in place (raises the geography and freshness ceiling without re-enabling scraping). Both are tracked in the changelog as they land.