The boundary is the whole point
Owners routinely assume that anything with a Houston mailing address is a City of Houston property. It is not. Large, heavily-rented parts of the county — Cypress, Humble, much of Spring — are unincorporated Harris County and run through the Harris County Housing Authority.
Sending a request for tenancy approval to the wrong authority does not produce a helpful redirection. It produces silence, and then you start again.
What is the same, and what is not
The program structure is federal, so the shape is familiar: request for tenancy approval, rent reasonableness, inspection, HAP contract, direct payment of the authority's share, annual recertification.
What differs between authorities in practice is the operational detail — scheduling, local payment standards by bedroom count and ZIP, inspector availability, and how re-inspections are queued. Those differences are not published in one tidy place; they are learned by doing it repeatedly.
Owners with property in both jurisdictions
A small portfolio spread across the county can easily straddle two authorities. That is workable, but it means two sets of timelines and two sets of relationships, and it is a strong argument for having one manager who already deals with both rather than learning each from scratch.