New Key/Refitting entire lock system

[hairyape1]

I only have one key for my car, so I want to get another, just encase i loose one. I would want to get a remote locking key as my current one isnt.

How much does it cost to have a key cut and coded with a transponder?

I have been looking around and its possible to get a set of locks with 3 keys off ebay of ~60 quid. Would it be possible to buy this and recode the ecu to match the new transponders? It is possible to do this?

If I could get a set of keys, locks and matching ecu. Could I fit this and then have no worries about coding transponder, or the ecu because it is already matching?

Many thanks
Ben

[Withnail]

I may be mistaken here, but as regards getting a set of keys, locks and matching ECU - I am sure that I have read on here that the instrument cluster is also coded. Would be grateful if someone would correct me if this is not the case - I have a passing interest in the answer to this ever since my sister's car (not Audi) was effectively scrapped soley due to an immobiliser problem and am also curious to know which components are coded to the transponder just in case the same thing ever happened to my car...