The reason behind asking value not being allowed is because there is a 90% chance this person has this item, wants to sell it, and asks its value as a back door to sell here. The reason why membership is required to sell here is because you pay for a membership so your information is known by the mods. By running the forum like this, there is a low chance at Nigerian princes coming here selling $3000 ultra rare 1 of 10 made blades with mastodon tooth.
At first I did not understand why they wanted us to pay for a membership to have full interaction here, especially messaging, but after it finally hit me, I find it a brilliant system and tip my hat to the mods by running their forum this way... I still have the lowest level membership only because I will start buying and selling more and will be divorced in no time flat! Lol