The seating is a mix of rear, forward and side facing.In South America, the extremes of climate are more marked and so, for comfort, the trucks are more heavy duty and usually enclosed.Generally you get what you pay for and the cheapest overland trips may not include extra costs such as entrance to game parks.The other thing to take into consideration when you're comparing prices is the truck kitty.This can cover accommodation (when not in a tent), campsite fees, food, and entrance to game parks or historical sites.Exodus claims its kitty is only for food - which is why the tour price appears more expensive than others - while Acacia Expeditions (020-7706 4700; promises "no hidden costs". Study the brochures, browse the websites and, if possible, go along to one of the slide shows that many of the companies put on regularly around the country.Essentially it's a challenge and an adventure rather than a holiday. A few companies run cushier options for those who really can't handle the idea of roughing it - usually a mix of hotel accommodation and camping - but, apart from these, the answer is yes.And you have to put the tent up and take it down as well, which is no mean feat if you've never slept under canvas before.
Some overland companies charge substantially more than others - Dragoman and Guerba (01373 826611; are at the expensive end of the market, which is especially noticeable in Africa where there is so much competition - but then their trucks are of a very high standard.
You also need to check details such as whether lunch is provided on travelling days and if any group meals are included. Apart from the obvious considerations such as the time you've got to spare and your budget, a lot will depend on the type of trip you want.
Some trips are more activity led, while others focus more on the cultural side.
Tents tend to be of the basic two-man variety, with built-in ground sheets and mosquito nets, and you have to deal with all manner of creepy crawly things that might want to kip in there with you.
But as you set up camp on the Bolivian Altiplano or beneath the spectacular peaks of the Torres del Paine National Park in Chile, the sub-zero temperatures and lack of washing facilities pale into insignificance.