Probably the best way to find out is to put up a price and look at the sales statistics, then after a while add some to the price and see if sales drops. Then also go in other direction and lower the price a bit and see if sales go up.
You would want to find that sweet spot where price is just right for your offering and delivers most sales. For any given item there is a certain amount of buyers, you would not want to divert some of them by setting price to high, on other end you do not want to lose earnings setting price to low and don't get more sales out of it.
That would be hard to get with conversations, the best way would be to try it out in the field and take samples and get to know what is your amount of unique buyers and how they react to your offerings.
Allot of websites are beginning to use AI algorithms to adjust prices adaptively over time to get to this sweet spot, it will probably not take too long before CGtrader will also experiment with that sort of implementations (if not already?).