When I first started my current character (a wizard) I gave them a potion that duplicated the effect of the supernatural toughness trait. At the time I didn't know the rules very well and my DM (IIRC) told me it would cost 2 enchanted item slots to make.

 Since then I decided to make a potion of inhuman recovery and asked my DM to confirm the cost. He couldn't seem to decide how much it should cost and came up with a house rule that I could have up to my lore skill in potions of that sort (based on refresh cost) and it would cost me the refresh cost in enchanted item slots for anything more than that.

 I'm worried that might be a bit overpowered though. Any thoughts?