First I will start with, I love this server. Small yet full, great Staff, and helpful.
*If an /auction function could be added. More an Auction House. Where players can leave deals up for an extended period.
*Player sell chests- Similar to the admin shop, but player run on our own Island.
*If neither of those are viable, you had mentioned certain objects to sell.
**Cobblestone - $1
**Saps - Oak, Spruce, Birch, Acacia = $2 ][ Dark Oak, Jungle = $3
**Logs = $4
**Charcoal = $5
**Cocoa Beans - Full Stack = $16
** Fish - Fish/Salmon = $3 ][ Puffer Fish = $15 ][ Clown Fish = $20
I was going to add Ghast Tears and Magma Cream, but i realized they could also be Farmed in the nether.