Apologies all as I'm sure this has discussed at length however I am still confused as to what is required.

I have bought a new key and transponder on fleabay as I only have a single 2 fob key. I have purchased a 3 fob key but I believe I need to have it coded to the immobiliser and also for the remote centra locking system.

I believe I need to get my SKC code or key code to have it coded? Is this correct please can someone give a definitive answer and potentially some one who may be able to help me

Probably find a local locksmith that can clone it from your original key.

Local timpson can do it

You'll possibly find that you need one of the larger Tipsons to have the kit to read the original /code the new one. A lot of the smaller ones won't have the kit.