Loan assumption - I need your help!!

[David Doucet]

Hello BP community! * I need your help and sage advice!! *

I have a chance to assume a freely assumable loan for a duplex at 3.25% loan rate with a balance of $214,000. It was appraised two months ago for 260k. I believe it only needs some minor HVAC work under the crawl space (reconnect two ducts and insulate existing ducting) and a few other touch up items that won't cost more that ~3k to fix up total. The seller would like to walk away with 10k (which I would have to pay out of pocket on the side). To assume the loan will cost $2-3k. PITI would be about $1,100. Assume 7% for variable landlord expenses.

Top unit (1/1) rents for $825 and bottom (2/1) rents for $1100.  

I have tried to find calculators/spreadsheets for this scenario, but can't find something to show me how I would do in this deal.

Does anyone know of a way to calculate this deal using existing tools or can they point me in the right direction for analyzing this deal?  I appreciate any thoughts, cautionary tales, or direction to head with calculations, etc.  *What else am I missing?!*