All my early cars were bought privately.
15 years ago when I was skint, 2 young kids and all that, and had a 13 year old Cavalier, I went to the auctions and got a Citroen BX Diesel for £2500 with about 97000 on the clock.
Kept it for 2 years then went back to the auctions and got a much better one. £3500 this time, 85000 miles, kept it for nearly 5 years to 140000 miles. Unfortunately I blew the cylinder head coming back from Sneck with a burst hose.
I would still buy from auctions if I was short of dosh but now I use a dealer, some of them go out of their way to help you if you're a regular customer .