I don't think anyone would purposely de-activate a gun that was still useable as it is a case of spending money on something to make it much less valuable. I have de-activated quite a few but I would stress that they were beyond all hope of restoration. As it is an offence to sell a firearm here that is in a potentially dangerous condition it is a way of at least preserving something of it and making it such that it is a wall hanger that anyone can own without certification and at least it does have some small value as decorative item. Better than having the whole thing scrapped and melted down; at least it still looks like a gun. It cost me just a little time and about 20 for the Proof House certificate of de-activation so that it can be taken off any Police records. I used to sell them on for between 50 and 75. I do see them for sale for 200 to 300 at some gun shows. They can be useful for teaching gun handling safety or as stage props too. Lagopus.....