You can request them from each county assessor or recorder directly, or use a provider that has already collected and normalized them. Realie sources county-level property records from more than 3,100 U.S. counties and serves them through one API with a consistent schema.
Property records in the United States are a county responsibility, which is why there is no single national database to query. Each county assessor maintains valuation and characteristic records; each recorder maintains deeds, mortgages, and liens. Going direct is viable for one or two counties and becomes untenable past a handful: every jurisdiction has its own portal, export format, field naming, parcel identifier scheme, refresh cadence, and in some cases its own fee schedule. Realie does that collection continuously and reconciles the results into one schema, so a query against Los Angeles County and a query against a rural Kansas county return the same shape.
The assessor values property for taxation. Those records carry assessed and market values, land and improvement splits, building characteristics, land use classification, and the owner of record as the county has it.
The recorder maintains the register of documents affecting title: deeds, mortgages, liens, and releases. Those records tell you what has been filed against a parcel and when. Most real questions need both — the assessor for what the property is, the recorder for what has happened to it — which is why they arrive joined on the parcel identifier.
The cost is rarely the data itself; it is the maintenance. County portals change layouts, rename columns, alter export schedules, and occasionally go offline. A pipeline that reads twenty counties directly is twenty integrations that can break independently, and breakage is usually silent — you discover it when a downstream number looks wrong.
There is also reconciliation. Parcels split and merge, identifiers get reformatted, and owner names arrive in inconsistent forms. Normalizing that once, centrally, is the work you are buying.