I don't know why this is or if I'm just dense but when I try to buy camp supplies(for example, I've tried other things) from inn at Vale or the blacksmith it won't let me purchase it even though I have the money to buy it.  It will show the item with the amount required to buy but when I click on the "trade" button all that happens is the coin dropping sound and nothing else.  I don't get the item, I don't lose money.  What gives?

if it is only camping supplies, you are most likely at your limit.

Your camping supplies are limited by difficulty setting.   Once you hit your limit you can't buy anymore. 

OK, thanks very much!