I personally prefer to buy cheaper cars possibly with more faults etc then go over the whole car myself.
Like the SDI I bought. Cost less than half the going rate of them normally but I've easily made that up on parts for it but I know the cambelts been done, bushes,suspension brakes etc has all been sorted. Just needs a good look to see exactly what needs doing.
If you don't want the hassle then IMO the person sells it best.
Passat the woman was so straight it was untrue. Full VW service history and she was loaded and every single tiny niggle was sorted.
My brothers gf just got rid of a Pug and forgot til the last minute it had no history as her dad had maintained it and to a good standard so there's good and bad and it's a case of a long check and good chat.
I ask tojack the cars up. Some let you and se don't.