I know I could as a dealer about this but I wondered if any of you guys and girls had any experience.

I believe it is very expensive.

I wonder if should you be buying a new car, could you request it at that stage when they are programming everything and it might be more economical.

I once had a Renault scenic. They don't have a key , but have a card which goes in a slot. This failed and Renault wanted a couple of hundred quid to replace. After a search on the interweb thingy I found someone in Wales who repaired it for £25.

I got a spare 3 button remote from a local company (Nottm) for £140 ..... programmed and ready to go. Not cheap but couldn't find anyone cheaper at the time.

The good news is Skoda keys are cheaper than other VAG cars even though they all have the same electronics inside. It also means you can get an Audi or Bentley key to work with your car :P... 

Thanks

Im not sure if you can obtain the 3rd key from the dealer. I think they offered 2 of them only... anyway, it will cost a lot.

If you get it done by some other company, it might be much cheaper.