Unfortunately, I don't know the market for English .com domains. What I would try to do is search for the price similar domains have been sold for, similar mean

Unfortunately, I don't know the market for English .com domains. What I would try to do is search for the price similar domains have been sold for, similar meaning of similar length and keyword search volume, CPC etc. For the German market there are some quite active Facebook groups where people sell (mostly German) domains. I befriended one of the bigger guys there and he helped me with an actual number the owner guy would definitely sell for.