£2k should be plenty for something decent that needs a bit of work, but try to buy before the spring rush to get the best deals. As already suggested, buy on the condition of the shell - everything else is replaceable (including bolt on body panels, though these are getting harder to source in decent condition). Make sure you do a HPI (there's a cheap one now - checkmycar or something?), look out for accident damage and spend some time reading all the paperwork from the car. A good set of paperwork will give you an insight into a car's history and may tell you of any major works that have been done on it.
As mentioned, engines tend to be pretty robust, but beware of the gearboxes - these tend to develop problems after about 150k if not looked after.
