What's the best approach to implementing a remote control lock?
This is not a hard project. Firstly you'll need to get an electronic lock.



They're pretty cheap (less than £20). These kind of locks require 12v to operate. An arduino can't directly provide this kind of voltage, or even the kind of current required by the lock, so you'll need a driver to interface.

Whenever I need a driver for this level of current and voltage (and especially if it's an inductive load as this is) then I always reach for my trusty ULN2803. It has 8 high current drivers, which is overkill here, but at least it gives you the option of actuating loads of locks. The other benefit of the device is that it has inbuilt diodes to cope with the inductive kickback when the lock switches off.