Flip a vacant lot, need advice/details

[Anthony Wick]

Details being offered to me: 

Vacant corner city lot. Privately owned. Sewer and water already ran by developer. 

Being offered to me at $65K. Potential to have quick sell for $80-90, or hold until next spring and possibly sell for $100k (rough figures, but comparable or conservative to recent sales). 

I would split this deal with a partner, who is bringing me the deal. 

What are the major concerns/things to think about here? Holdings costs should be minimal, as we'd pay cash. Still working out closing costs, possibly paid by buyer when we sell. So, a possibility for a quick $15-20k, give or take. No? I'm aware of short term capital gains as well. 

I'm generally a buy and hold multi family investor, so this is new to me.