Should I flip my brother in laws house or just have him sell it?

[Lisa Caracciolo]

I was hoping to get some advice. I just feel like I'm not looking at this from all angles and I want to make sure I'm coming to the table with a win-win scenario. My brother in law is selling his rental; it needs work (probably about $50k) and he wants to net at least $300k when all is said and done (he owes $215). He was going to sell it as-is on the MLS as-is, but he was thinking he could list it at $500k, but I told him that investors would probably offer closer to $430k (as I believe ARV is around $550). Then he was going to see if I wanted to buy it from him and flip it myself, but I don't think that I could make any money on it if I bought it from him as I would have closing costs, holding costs, etc. that would just push the profit margin too slim. He brought up an interesting idea of just flipping it together: aka....I'm boots on the ground here and would run the flip completely and put up the money for rehab and he would just be almost like a silent partner (he is out of state and doesn't really have time to deal with it anyways). I'm wondering if it's even worth it or if I should just advise him to sell it on the MLS as-is....I know I'm missing something as this seems like a great opportunity, but I can't seem to make the numbers work.

It's on 7th St and Greenway 3/2 1550 sq ft with a pool on 15,000 sq ft lot.