I'd give him the legal notice, and return his deposit (yes, it will be painful, but if you don't have proof, IMO it's a lost cause, not worth the hassle/stress) , and offer him a sliding scale, $400 if he moves out next week, $300 if he moves out in 2 weeks, $200 if 3 weeks, contingent that he cleans up the place too.  

For cheap money I’ll go through some pain.

It was a domino effect - slow an painful for the property owner when the deal goes south.

@Chris PurcellYou're setting yourself up for a painful fall if you plan on doing this yourself now.

I've been using MySmartMove (Transunion) for awhile -it's pretty good, though occasionally a pain to use. 

For me, the pain point of finding reliable help is alleviated when someone genuinely wants to learn. 

Everycould use someone else’s experience instead of making the same painful and costly mistakes.

I would love to connect with people with the same passion and hunger to learn!!

@Austin Youmans Thank you for your advice.I have estimated repair cost $5k since the property looks good, it just needs some cosmetic repair and most of them like paining, gardening,...

-Ask him why he's selling (this will likely bring up a pain point for the seller, which is good for a sale: bad property management, bad tenant experience, doesn't have time, no longer lives in the area so he/she can't properly run the property, etc.)