Numbers look good, gut still feels wrong

[Sean Cassidy]

I'm looking at a deal here. It's a 3 unit, one of them is gutted, the other 2 are ok. It's a C building for sure, but in a decent area. It could be quite nice with some effort, and it already has cash flow from the renters that are in place.

I ran the numbers and they look good. But my gut feeling was wrong. So I built in a 50% markup on my rehab figuring this will cover pretty much anything that pops up, numbers STILL. LOOK. GOOD. Buuuuut, my gut still doesn't like it. 

So I got some comps and changed the 70% rule to the 50% rule just for kicks. Using 50% of ARV minus my inflated rehab estimate my calculator tells me to offer the seller an extra $100.00 over asking price. My gut still says not quite right.

I can't tell if my gut is thrown by a rare home-run, or if there's something I'm missing here. 

39.9k asking

45k rehab (with 50% markup) 

125k+ for comps

This alone looks good.

If I offer 35k they'd take it. Why is my gut saying no... What am I missing? !