You can trade with a Treasure, you don't need a MM than.
Its safer for both. You put the code into the treasure and open the treasure cost egold for the buyer if he pay to open, you will recieve the e*gold. Hope i helped you.
Edit: Maybe some user offer you less money as you can reach.
You can get max. 3750 e*gold.
I advise you to demand for 3500.