Item Upgrade shop - Help

[Fulla]

What would be the easiest way to do this.

A building with a hero inventory if 1 slot.

You place your item inside and then an use the buildings ability to upgrade.

The cost depends on the base cost of the item. So e.g.

500gold Item - costs 500 to upgrade
700gold Item - costs 700 to upgrade
etc. etc.

How can I do this with triggers so its made clear how much it will cost to upgrade and make it so it only works if player has sufficient gold?

thx

 

[qwerty]

why, the EotA way of course. when the hero puts an item into the altar, create floating text telling them the price to upgrade. if they use the "Temper" ability, then check if player has enough gold. if it's true, remove the item and give a new one, if not, display text to player: "Need more gold."