helppp !! Duplex but for sale as a single family ??

[Isiah Ferguson]

I came across a single family with a 3/2 about 1200sq. There's a basement with a full kitchen, bedroom, and great size living room with a potential for a second bedroom. The main living has a door access to the basement with a lock. The basement its own has a front door, backdoor, and own drive way. But it only has 1 A/C unit connect to the house. It was listed for 310k 2 months ago but now is at 275k. Potential rent for the 3/2 is $1600-$1700. The basement apartment can go for $900-$1000. The basement need some work. The main living space is moving in ready. I'm thinking to put a offer in. What should I do ? any advice ?