Jonas Dannenmaier

I run Ferinus, an underwriting platform for small multifamily in South Florida (under $10M). My thing is rebuilding the real operating numbers behind a deal from public records, the parts a broker OM tends to smooth over: parcel level property tax and the Florida reset after a sale, insurance on older coastal buildings, and a full gross rent to NOI reconstruction with every figure sourced. I post here about what actually moves a small multifamily deal: DSCR at today's rates, debt yield, breakeven occupancy, and the tax and insurance lines that quietly kill cash flow. If you are buying 5 to 50 units in Miami, Broward, or Palm Beach and want a second set of eyes on the math, my inbox is open. No pitch, I just like getting the numbers right. ferinus.com