How does one judge the worth of a non-magical but superior item?
Let me explain: A normal set of masterwork thieves' tools confers a +2 circumstance bonus to Disable Device. They're 100gp to buy.
I recently received a set of beyond masterwork thieves tools that conveyed an extra +1 beyond masterwork-- a +3 circumstance bonus to Disable Device. It's a non-magical bonus-- so it works in anti-magic zones or in suppressed areas. It's also an extra +1 bonus on an item that isn't available in a more powerful state. But I don't know how to determine how much that extra bonus is worth.
Not being able to quantify it really getting on my nerves.
Ok.. how about bonus squared * 25 so 3*3*25 or 9*25 or 225
bonus * 50 = 3*50 = 150
Or just ask the dm how much they're worth. he gave them to you, so its his decision what to price a non-standard item.
Its not really a formula that you can solve anyway. Look at the portable alchemist lab compared to the alchemist lab.
Portable = 75 gp = +1 circumstance bonus to craft (alchemy)
Lab = 200 gp = +2 circumstance bonus to craft (alchemy)
mw thieves tools = 100 gp = +2 circumstance bonus to disable device
There's no good formula for figuring out the bonus of non-magical items, if there was, I'm sure the people at paizo would have used it and we wouldn't be discussing this...