How to save £500!

The key to our sportage snapped several years ago and so we used the replacement until yesterday that snapped too! Spoke to the garage and for a pair of replacement keys it was going to cost us a trip to the garage and £540! I nearly fell over. A little bit of googling and good old amazon prime and 2 new blank keys arrived. Simples I thought...however I had to utterly destroy the old keys as they were glued together, then after building the new ones I was rather distraught and sweaty to find the new ones wouldn't start the car. Turns out they hide a cheeky little chip inside the key fob, separate from the electronics!! Found it, dug it out, added it to the new fob and boom, 2 brand new keys, that look identical to old ones, for £12. Now how can I convince Amy that I should spend the saved money on board games!!