Got another idea:
-game is missing one kind of bag like money pouch. It should be made out of leather and string just like seedbag and could be equiped in place of belt. SO instead of belt you can wear "money bag". This money bag could or could not be stolen when one is killed that is remain to be talk over.
-if character is having that bag equiped ,they could put in money with picking it up and right clicking on it. On the bottom of inventory there should be only numbers of how many coins is on character and not like empty slots to put something in. When left clicking on each number, you open a popup window that let you type in a number how much of coins you wish to pick from bag and after that just button for picking it up.
+: would make easier to carry around metal bars in large quantities and some ppl would like to go to "shopping" with empty inventory and just some money in pocket to get some stuff from vendings.
-: hard to manage quality of coins (metal).
