It sounds like you need to put your business head on and tell him what needs to be done to fix it properly. Give him a realistic cost including pricing for any incidental fixes that you think will be necessary. If he can't afford it he can't afford it, you're not a charity
I have to say I agree... It's not your fault that he's failed to maintain his vehicle properly... Looks like it's caught up with him and bit him.... Out of all the options, a pair of alloy covers is by far the cheapest!!
Yes boys you're right of course, but that doesn't stop me trying to come up with the best option for him.