Heather, I think you know me well enough that I could give him the blues over that whining about tools. You have to nip this in the bud and the only way to do so is to do your homework and when you have some prices, then say, Matt, here's what a used grinder, comparable to what I purchased you 10 years ago is going for.
Tools that are over a couple of years old, have been left sitting in sheds for a period of time, aren't worth as much as slightly used or new ones. Also, if they were sold at yard sale, you certainly wouldn't get full price for older tools like those he's whining about. He needs to get real about this staff and besides, if they had really mattered to him at all, he would have taken them years ago. Heck, you could have charged him a storage fee if you really want to split hairs over this stuff.
Trust me, I would give him one boat motor and tell him the other one is yours and drop that sucker right at his truck and say here you go and walk away.
This man really makes my blood boil over such stuff. Really reminds me of some of the antics my xh tried to pull on me. They should know that we aren't stupid about such things.
BTW, I'm glad I could make you smile.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.