Short answer: NYC's Local Law 18 makes whole-unit short-term rentals illegal in most Class A residential buildings. Lenders read your certificate of occupancy to see which class the building is, and underwrite accordingly. Airbnb income may count for nothing.
A real example
A Brooklyn brownstone operator wanted to refinance based on a $3.5M value and short-term rental income. Comparable sales suggested roughly $1.9–2.4M, and the building's CO class decided whether the rental income could be used at all.
What to do
- Pull your CO before anything else.
- Expect lenders to underwrite to long-term rents if the STR use isn't legal.
- Net platform fees out of your income figures.
Related: DSCR loans