As a general rule, finding a car which uses less fuel is preferable to purchasing one that uses lots of fuel. Most modern economical cars can cover more than 100 kilometers per gallon, and although the majority of these have diesel engines, small petrol engines can be almost as economical.

The plus point for petrol powered cars is the abillity to be converted to use LPG or CNG which is a much more econimical solution, aspecially for petrol powered cars with large engine capacities. As a result you will find a number of used cars which have already had this conversion.

Extra space can be a waste, with bigger cars often costing more to run than smaller ones, so think about who you'll have in the car. For adults with occasional passengers, a city car or a supermini could be just right. A family saloon is fine for four or five. Small MPVs, also called people carriers, and most 4×4s also seat five, but many can seat seven in comfort.

If you normally only use a car for short journeys it's probably best to buy a model with a small petrol engine as on the whole they are cheaper to buy than diesel powered cars and are increasingly economical. If you usually complete long trips and motorway driving, the extra cost of a diesel makes sense, as the extra fuel economy will fund the additional outlay in the long run. Low-powered cars often use more fuel at motorway speeds than bigger, higher-powered cars as their small engines need to work much harder.

While a small car usually has just enough space in its boot for a few shopping bags, a large family saloon or hatchback car can take you and your passengers on holiday or accommodate a few pets. It's worth making sure how much space a car has with its rear seats in place, and folded down for more luggage room.