If you want remote central locking but not a full alarm system the AVS Keyless Entry system is the answer.
The system will simply lock and unlock all the doors in the car from the AVS remote (some cars do need additional parts). It comes with two waterproof rolling code remotes with buttons that are clearly marked and easy to push. Many keyless entry systems come with hard to use or unreliable remotes.
Plus only with AVS do you get a 3-year warranty on not only the system but the remotes as well. And by choosing an AVS system you get the support of a nationwide installer network and product support.