We actually have a sellback store. Which buys items at 50% of the regular price. Also, the prices here are actually quite cheap, the gold gaining system here just takes a bit of getting accustomed to.

And I think an exchange like you're thinking is in the works. I can never remember. So don't take me at my word for that.

You can sell CIs, the items you buy with Mennies for gold in the Exchange.

On the daily change, usually those have no items anyone wants. So they just clog the system with a lot of unwanted items.