Traveling on a budget can be quite a challenge.  When you try doing a successful cross country journeys, sometimes it can be a pain to take public transportation.  Trying to keep a strict schedule can impossible with the long lines, engine breakdowns that are out of your hands and last but not the least, the general nuisance of other people getting in your way.  Sometimes it is easier to just wait until you have enough money for renting a car before you head out.

A 4×4 can come in handy on those off road routes that are less traveled.  If you wish to have the simple convenience of your own car without doing much damage to your budget, a simple Toyota Rav4 will do. If you have money to splurge, go all out on a BMW X6. If they did not raise the road tax on trucks in the UK, I would love to have one of those babies in my garage. If you are after speed and wish to see more than what is on your ideal itinerary, go for a Subaru WRX. It will still serve you well in off road situations which is good considering you have sacrificed some leg room. You can settle of a Toyota Sienna although I am not sure how that will do in rough terrains. You can stick to main roads if that will save you more time than driving in the woods with a car that is meant to be a suburban family wagon.

Traveling with a rental will allow you to have more control over the time frame that you are working on, with long queues out of the equation, and the hassle of other people, if you still manage to mess up your schedule, you have no one to blame, not even the car, but yourself and your possibly lousy driving.