Yet this is a "loved up" forum, where members happily buy and sell to and from each other! I don't see a difference really, other than conscience playing a part if something unexpected happened. Like i-CONICA, I wouldn't like to sell anything under par, unless I fully appraised the buyer first.
I once sold a car to a friend, and left my private plates on it until my new car was ready for the transfer. My partner had a phone call from a friend of hers, worried that I was having an affair, as she had seen my car parked outside of someone else's house every night for a few weeks!
That reminds me of another instance where I bought/acquired a 1963 Hillman Minx from a friend ( can't remember the exact circumstances now ) which had a pre-suffix number which he said he wanted to transfer off , only he never did in the three or four years I kept the car ( it was used by my ex , with whom I was living at that time ) . It was only after that car was sold on he promptly said 'but I wanted to keep that number' .
This was the same friend who dragged me along to view a Triumph Herald he fancied buying , only it turned out when he got there he had no money , so muggins ended up paying the £45 asking price ; I took the car home and parked it on my drive telling him he'd get it when he gave me the money . Of course , the money was not forthcoming so I registered it to myself and ran it until the MOT expired ; it turned out the chassis was rotten and it would have needed a lot of work so I just scrapped it , but I got six or seven months use out of it and got £25 back from the scrappy , I think I had put two remould tyres on it but that was all , so still cheap motoring .
I've also remembered that my sister Lesley , the one who likes Volkswagens , passed a couple of aircooled Beetles onto me , we each had a succession of them , our parents having had them since the sixties , as well as Mercs and other vehicles , and I also passed my Audi 100 onto her , which she then ran for a couple of years ; now that I think of it , there was also a MK I Polo hatchback and a Derby which passed around the family , and a yellow Mini which I took pleasure driving around in wearing a tweed jacket , often getting people to point in my direction and giggle 'Mr Bean' , which I found amusing .
Most of these cars transferred ownership , but then , as now , within my family we have been pretty free and easy allowing use ( subject to insurance cover ) of each other's cars .
As also mentioned above , I have sold at least one car ( the W124 E250D ) to a forum member , and I know that car lived on to be sold on again ; besides I have bought lots of stuff from members of this and other forums .