i have a extra keyless entry/start fob for the lancer with the tech package. Offer a good price and its yours. I traded in my 08 lancer with only 1 key so i have a extra.
i lost it at a golf course so i thought it was gone forever, but someone the next day someone found it!!!!
my friend has keyless entry on his volkswagen. its one of the higher end models, i cant remember the name. but i know he said it was $100. obviously it will vary from make and dealer, but just a heads up its probably not cheap. plus they have to reprogram it... ugh...