Talk to your partner about it before rushing to any legal actions. Maybe his father can make up for it by completing the projects (if wanted) and you could somehow make due with the water issue?

Talk to your partner and sit his father down, he needs to be told and understand that what he did was unacceptable. This is your house, he had no right to start projects in it, especially since he clearly appears unqualified. I wouldn't trust him to finish anything considering he already did major damage, so if it were me, I'd be asking for compensation to finish and fix everything. And if it comes to it, court might be needed, he ruined your​ new house, he needs to be held responsible. In my opinion, you don't get special treatment because our blood shares microscopic similarities, you did me wrong, you make it right, end of story. When you **** up, you take responsibility and fix it, and if you don't, expect to be forced to, no matter who you are.

Something tells me he MEANT to destroy the kitchen. Does he harbor any bad feelings towards you and/or your partner?

Not that I'm saying this was the case in this instance, but...I've seen this happen a lot with the deadly combination of redneck dads, tools, and beer.

was it one of those situations where he says 'lets just do this quickly' and you are too polite to say no and then it is too late? I totally get that, and he should not be pressuring you into it. if he decided to do these things and you didn't tell him you didn't want to then I would say it is not entirely his fault. but he shouldnt have pressured you or presumed.

don't let him leave til he fixes them, or make him pay for the repairs.

"No". Works wonders.