I think I know what's going on here. It kind of bugs me too but it makes sense. Lots of times for sale adds get posted with a price (they all get posted with a price) and then when the item sells the price is removed and just the words SOLD are present. So when you go look back for items that have sold previously to get and idea of what the number was/is etc.. it's gone. Makes it hard to research parts and prices even just for rough ideas.
I get it though, not to pick on this add at all, it did have a price I remember seeing it (I'm not going to quote it because I don't recall 100% what it was) but it was replaced with SOLD. Lots of times the price posted, asking price, might not be the selling price. I might ask $100 for something but it sells for $75 I don't want to put SOLD next to my $100 asking price, cause it's not really true, nor do I want to post the actual selling price because that's between me and the buyer.