The smallest and cheapest are campervans and typical examples are Toyota Hiace or VW based and come as either high roofs or pop-tops. The Hiace is often the vehicle of choice for a campervan but it does suffer the disadvantage (when compared to a VW) of not having a "walk through" from the driver's cab and not being able to swivel the driver and passenger seats around for extra seating. Campervans are certainly the easiest to drive in terms of external size and parking space but suffer from a small amount of internal space. In most the bed has to be set up each night. However, even with the latter, there are degrees of difficulty - some manufacturers have a seat
that simply folds out with the flick of one lever, in others it's a case of removing tables, fitting the base and lifting and fitting cushions together. Give things like this good thought - if you are planning some serious long term travel, a campervan might be the cheapest way to do it but making the bed up every night, might become a very irritating chore. Somewhat larger in size are units built on Ford Transits, Mercedes Benz Sprinters, Fiat Ducatos or Ivecos. With these larger vans, mostly high roofs, the definition of campervan or motorhome becomes more blurry.
One definition that makes some sense, is if it has a shower and toilet cubicle, then it's a motorhome! Whatever they are called though, many people like these size vehicles because they are large enough to be comfortable and small enough to be easy to drive. In some designs, the bed has to be set up every night, but in others (usually with front swivelling seats), it can be left made up In some of the campervans and smaller motorhomes, there's sometimes a choice of motor - either petrol or turbo diesel. In larger rigs its turbo diesel or nothing. When there's a choice though, and you are planning on putting a few miles
on the clock, then turbo diesel is probably the preferred option.