An 8 year old vehicle will always depreciate less than a new one. That's a plain fact that applies to all, regardless of whether it's a car or a 4x4. However, when comparing vehicles of equivalent age, 4x4's often hold their value better. On the other hand, running costs will no doubt be somwhat higher for a 4x4, not only because the additional weight results in significantly higher fuel consumption but also insurance and servicing will be more expensive, too. Although I've never regretted my change from a Vectra (old model) to a 4x4, my fuel bill has almost doubled when driving solo. When towing, the difference is not as big, mainly because the weight and size of the caravan made more of an impression on the struggling car which had to mobilise every available horsepower in order maintain acceptable performance.