Cheapest thing to do is hook it up to your house VCR and TV, if you pretty much know when it will happen set timer record and voila. If not, best thing is a kit that has a PIR sensor aswell, this way it should only record when there is movement.
You can get very good and very bad for your money, for instances, I have a friend who bought a black and white one for £45 a few years ago and it was really poor, I bought my grandpa one from Makro about 2 years ago for £25, fulll colour, microphone etc. He has it as an access system I designed for him plugged into a 6" screen and long play video with date stamp. Any problems he knows to immediately hit record, set off his alarm and phone the police. THough obviously it can't record over and over as a long play video doesn't last long enough.