Write or Wrong, that is great that he likes to fix things, maybe he can work with an electrician or plumber? Do you have any friends that would take this on as a huge chesed, ask your son if he has time to help him with a job?
Your son is going through a hard time right now. Hang in there. Make sure he knows how much you love him. I think after a while he will get sick of doing nothing. The weather will turn cooler and it won’t be so much fun to hang out at night when it’s cold out.