I can answer a couple of questions for some despite having not done this particular experience. Your car choice can dictate price. My personal opinion is that additional money is better spent on getting more laps, in the less expensive cars. Unless you absolutely love a certain model car, you'll find that all of them will exceed your limits, and give you a great thrill. If this is your first opportunity to be on a track, you'll find the sensation of speed will be there even on the slowest sections. Nothing quite beats the feeling. It can be enhanced with a good instructor. I'm unsure if the folks riding along seek to teach you, or whether they are simply for general guidance and safety. I'd wager most will teach if you are willing to learn.