This ain't some guy I met down the pub he was my best man at my wedding and will be his father to my kid. So I kinda trust him in fact I trust him more than my wife to look after Betty lol.
If he writes it off it's only metal and would be more worried about him than the car.
Running costs tax & insurance split 50/50, fuel top up when you park up. I can't see either of us putting mega miles on her so things like tyres are probably not going to come up, general servicing we would do together and split parts cost.
I know there will be unknown break downs and repairs eg the clutch I just put in, I can't ask for a 50% share as its my car so I will end up paying the lion share of all big bills and I accept that. The way I see it if I ended up with £50 off a £200 bill I would have had to do it anyway so its a few quid in my pocket.
He works weekends so wants a weekend car during the week when he is off and I'm at work, so I still get a weekend car at the weekend.
I'm sure there are things I should be thinking about