Dunno the exact details on what the deal was with your buyer, but as you say further up your a bit new to all this internet stuff, I cant see why you might have concerns.
But mainly giving your bank details is safe, ie sort no and acc no, the same no's that you would be happy to hand over to anyone when paying with a cheque for example.
paying for a car with paypal, can be ok, but to me seems to ring alarm bells, as its really does favour the buyer into claiming his money back!
Thanks for the advise. Yes I think you are right. Never mind live, and learn