
I would appreciate an option to set a minimum and maximum price for a given item.

per item?

I would also agree to this. I want to set a minimum and maxmium price for a given item.
I am using all 3 player/shop/auction GUI and I want to specifically limit the price of the items.
For example:
ShopGUI has Diamond for $800 each.
PlayerShopGUI can only go as low as $600 each.