Turnover is the full cycle of one tenant moving out and the next one moving in: the move-out inspection, the repairs and cleaning, the marketing of the empty unit, the showings, and the new lease signing. It is the most expensive routine event a small landlord runs, because every step either costs cash or costs rent while the unit sits empty.
In practice
Say a tenant on a $1,500 unit gives notice and moves out on June 30, and you get the next lease starting August 1. That is one month of lost rent, so $1,500 in vacancy before you spend a dollar on the unit. Then the work: paint and a deep clean at $700, a carpet clean at $180, two small repairs the move-out walkthrough turned up at $220, and re-keying the doors at $90. Add a $150 listing photo and screening cost and you are at $1,340 in cash. Stack that on the $1,500 of vacancy and this single turn cost you roughly $2,840, or close to two months of rent.
That number is why the calendar matters as much as the checklist. If you had turned the unit in two weeks instead of a month, you would have cut the vacancy line in half and saved $750 on this one turn. The cash repairs are mostly fixed; the lost rent is the part you control by moving fast.
Why it matters to a small landlord
On a portfolio of a few units, one turn a year can erase the cash flow you spent twelve months building. The two levers are speed and retention. Speed means having the repairs scheduled and the listing drafted before the keys come back, which is the heart of the full turnover cost and process breakdown. Retention means a turn you never have to run at all, which is why the math on keeping a good tenant through a renewal almost always beats the math on a higher-paying stranger. The deductions and the deposit also live here: document the unit's condition well enough that any charge against the deposit holds up, then close the loop with a clean security deposit return letter.
Turnover is really three glossary terms running at once. The repair-and-clean phase is the make-ready; the days the unit sits empty feed your vacancy rate; and the bookend documents, the move-in and move-out inspection, are what decide whether you keep the deposit or hand it back. Run all three on the same short timeline and a turn stays a line item instead of a setback.