I've got an arborist friend who cut down a tree in my front yard last week. He wouldn't let me pay him (I was quoted $450 by a company last year), so I want to buy him something to say thanks. As far as I can tell he's got his basic gear covered and carries some pretty nice saws... I'm new to this, do you have any recommendations of consumables, upgrades, etc., that would be on your wishlist in a case like this? I know it's hard to tell without knowing what all he has (I can scope it out next time I'm at his house), but any general suggestions are appreciated.