I can see both sides of the argument here. On the one hand, I don't see what the problem is with telling people what your car sold for - it's not going to decrease or increase your standing in the world in any way, it's just a transaction, and knowing what our cars are selling for means it's easier to correctly value them for insurance purposes as well as decide upon a price if sale time comes around.
On the other hand, there could be any number of reasons an individual doesn't want that figure to come out....if it was me, I wouldn't care about you lot knowing, but if Leah found out I'd just realised a hefty chunk of cash, then Barbados flights and hotels would be the day's number one priority So: no harm in asking, so long as you realise you might not be told.

In this case, I spoke to Gordon (whose car it was) before and after the sale, and he didn't even give me the actual figure he achieved, so it's fair to assume he doesn't want people to know. However, I can tell you that I advised him to ask more for it based on the price of a similar-spec turnkey car from LB, and the long wait should you succeed in placing an order. But he set a figure, and received multiple inquiries - therefore I think it's reasonable to say it wasn't overpriced...so I think you can make an educated guess from that