Used conventional turnover in my 55-plus model. Vacancy loss came in double.
Small deal, 44 units, age-restricted, secondary market. I underwrote 8 percent economic vacancy because that's what I use for conventional garden apartments in that market and it has held up for me across four buildings.
Actual year one economic vacancy was 15.4 percent. Not because occupancy was bad, physical occupancy averaged 92. The problem was days vacant per turn. Conventional turns in my other buildings run 14 to 21 days. In this building they ran 47 days average, and two units sat over 90.
The reason is the qualified applicant pool. Age restriction removes most of the market. Then the applicants who do come are moving out of a house they own, so their timeline is tied to a sale, and they don't sign a lease and move in three weeks. They tour, they think about it for two months, they tell their kids, then they sign for a start date six weeks out.
On 44 units at an average $1,340, that vacancy gap cost me about $52k against budget in year one. Missed my debt covenant test by a small margin in Q3 and had to have an uncomfortable conversation.
What I'd do differently: underwrite days-to-lease from actual comps in age-restricted product, not from my conventional buildings. And keep a bigger operating reserve in year one on any product type I haven't run before.