Dirt Trading For Items?!

I had to do this twice so it won't be too detailed.

Dirt Trading For Items, or DTFI for short, is a system that allows you to give us dirt and we'll give you an item in return.

The ammount of dirt you need depends on the item's sell value.

Copper coin = .5 dirt
Silver coin = 50 dirt
Gold coin = 5,000 dirt
Platinum coin = 500,000 dirt

There are also sales and coupons, you know how those work.