I've noticed that bjd's hold their value pretty well. Most of the used ones I've seen cost the same as direct from the company, without the long wait though. I'm curious to know if the OOAK bjd's hold their value that well or if they drop like a shooting star out of the gate like so many of the OOAK sculpts seem to be doing. Any knowledge on this topic would be much appreciated.
I think it depends on the brand or the sculptor name. Like for example Volks One-Off, which the secondhand price will be more than the original price, at least you sure it won't go down much. Or maybe some known sculptor who have sold lots of doll and suddenly make an OOAK, surely somebody will want to buy that sculptor work. For those who still unknown, I guess as long as the bjd sculpt is nice and well-liked, it can still hold the hold the original price. But can't hope too much for it suddenly to be very popular and high in demand, since nobody knows the sculptor yet and only making like 2-3 ooak doll won't make him/her suddenly popular. This is my point of view though, just based on what I see and think. So probably somebody else can help better than me.
Whether anything sells well or not depends on how appealing it is to other people. A doll might be one of a kind, but if other dolls look much better and cost much less, chances are the OOAK won't sell well. Another aspect is popularity. Like, if Enaibi put a doll up for sale, a lot of people would be crowding to buy it, because a lot of people love her dolls and her aesthetic. If nobody knows your doll or your work, who will notice if you put something up for sale? (not "you" in particular, but anyone) These are just things to consider.
