Not really answering your question, but if you want to have a go off road. Why not join a trials club, an ALRC affiliated one. There are loads and most run at least one trial a month.
Now here's the clever bit. You don't have to compete. Just offer to help setup a trial (assuming they setup the day before). Chances are, for the cost of your annual membership you'll get a whole day playing and learning off road techniques while setting up an RTV.