No HAP contract until it passes inspection, so the vacancy risk sits with the landlord either way

The sequence you described is the sequence. A tenant with a voucher finds the unit, submits a request for tenancy approval to the housing authority, the authority inspects and checks that the rent is reasonable, then the housing assistance payments contract gets executed and payments begin. Nobody can pay you for a unit that hasn't been approved.

What landlords do to shorten the window is mostly front-loading. Have the unit genuinely finished before the request goes in, because a fail resets you into the queue. Hand the tenant the paperwork you're responsible for the same day rather than a week later, since an incomplete packet sits. Ask the authority whether they'll accept the request while your make-ready is in its last few days, because some will schedule on a promised date and some won't, and that answer is specific to your authority.

On the first payment, ask two things in writing: whether payments run from the effective date of the contract or from the date of execution, and what their normal lag is between execution and the first deposit. Some authorities pay a prorated amount back to the effective date, and if that's how yours works, part of the vacancy you're worried about gets recovered. Some don't. It's worth knowing before you decide how you feel about the three to seven weeks.

And yes, the reliability afterward is a real part of the trade. It doesn't make the carrying cost disappear, it just means you spend it once per tenancy rather than every time a market tenant's paycheck wobbles.

The proration question @rena-guide raised is the whole thing, and it is the one owners almost never think to ask. If the effective date is the day the unit passed and payment is retroactive to that date, your seven weeks turns into maybe two of real loss. If it is not, the seven weeks is seven weeks. Same program, two very different numbers, and the only way to find out is to ask your specific authority.

People usually come to this asset class looking for income that does not behave like a second job, and the lease-up sequencing is the part that does. Three to seven weeks of unpaid coordination per turn is real cost, and it belongs in the underwriting rather than in the surprise column. The question worth settling is whether that load is front-loaded once and then genuinely low for years, or whether annual recertification and reinspection bring a smaller version of it back every year.

@priya_n21 a smaller version, yes, and how small depends on the authority. Annual reinspection is a scheduled visit you have to be available for or provide access to, and the recertification paperwork mostly lands on the tenant, though you will get asked to confirm rent and utility responsibility. It is hours rather than weeks. @carlos_nunez, the compression that actually works is building the make-ready punch list off the inspection checklist rather than off what looks finished. The failures are almost never cosmetic, they are the same eight or nine items over and over. The other thing worth asking your authority is whether they publish the inspector's checklist, because some hand it out and it makes the whole timeline predictable.