the key fob is about £20-60 and the reprogramming is no more than £60 on a CLIP (5 minutes work max, plug clip into car then clear authorised keys, then program each new key into the cars
(remote start (3 button) keys are a bit more expensive than standard 2 button keys)
(prices will vary depending where you are, or how much your dealership thinks it can fleece you for)
key fobs are now covered by additional protection against key cloning and car theft by having the VIN pre-programmed by renault before new keys are dispatched to dealers to do the final car reprogramming.
you only need a new set of keys and to have the car reprogrammed, not have the main alarm reciever and control box replaced, i think they are taking you for a ride on the quote.
(unless renualt have really now gone overboard on theft protection, in which case you must put in a insurance claim for new keys and Alarm module replacement).
as i stated above, contact all your regional renault dealers for a price for the new keys and recoding the car, as they may vary.
there still are some locksmiths that can recode new keys to cars, which will be cheaper than dealerships.
but keys will still have to be supplied by the dealership(pre-programmed).
All car doc's are needed by the dealership to get the blank keys ordered.
will your insurance co (home or car) cover your lost keys, as most home contents policys now cover key theft, as do car policys.
These days its more likely that they will target your keys to get your car as appossed to going after the car direct(which is now impossible to hotwire).