Key/Fob

Having recently purchased a second hippo i am going through the list of things to sort out. One of the main one is i have no spare key/fob.
Whats the easiest way to acquire a second set without costing a fortune?

It may be dependant on the year/modle, but there's an outfit that will send you a new key and a box of tricks that plug into the ODB socket that programs the key in - you then send the box back to them.

I'm not sure if this is just the key, immobiliser or locking/alarm remote. But the price is are very good. Worth a Google.