The detailed report they produce will highlight any exterior damage, or problems with the mechanical parts. If the used vehicles are in good condition, the inspection will offer peace of mind that they are roadworthy and safe, but if there are any problems then you can walk away from the sale, or ask the seller to rectify them or take money off.

If you don’t wish to pay for an inspection, it’s important you take time to check the car over yourself. Try to be as thorough as you can with your checks both inside and outside the car. The AA’s vehicle inspectors test up to 206 elements of a car, which shows just how much there is to look at.

Always go for a test drive, trying the car out at different speeds when safe to do so to check the components, and listen out for any unusual noises. You should also drive the car on some rough ground, such as a gravel car park, to get the suspension working and expose any worn components by way of excessive noise.

Carry out an external inspection by checking the tyres, lights and ensuring the windscreen wipers work.

Top points to be aware of if buying privately rather than through a dealer

If you buy from a dealer, you are protected by the Consumer Rights Act if something goes wrong, but this is not the case with a private seller. The Act entitles you to a repair, replacement or some money back if a fault comes to light in the first six months after purchase as long as the problem was present when you bought the car.

Some dealers offer warranties to cover the cost of repairs over a set period of time. You could consider getting one yourself if you buy privately, in case something does go wrong.

When buying privately, ensure they are the registered owner of the vehicle by going to their address and checking it matches what is on the car’s V5C document. Always be cautious if the seller wants to meet you on ‘neutral’ ground such as a service area or lay-by somewhere, as the car may be stolen.

Most important questions to ask the seller

Whoever you buy from, always ask about the car’s history, any accidents or recent repairs.

If you’re planning to buy a used car, you should ask to see the car’s service and MOT history and ensure the recorded mileage aligns with the car’s odometer. Check through all the documents to ensure they tell a consistent story which matches the vehicle, and be cautious if you cannot see the full history.

It is possible to carry out a lot of research yourself online. Online history checks, such as those offered on the AA Cars website, will confirm the mileage and number of previous owners, and will confirm that the car has not been stolen, been in an accident or written off. It will also tell you when there is no outstanding finance to be paid.

By entering some basic information on the DVLA’s online vehicle enquiry service, you can verify if a car has been taxed and had an MOT. It is also worth checking online to see if there have ever been any manufacturer recalls associated with the particular make and model.

Five most expensive car repairs

It’s always vital to ensure there are no faults with the car you are buying, as some repairs can be very expensive. Below are five of the most expensive car repairs, and how much they can cost.

Automatic gearbox: The gearbox is mechanically complex, and repairing it can sometimes cost more than the car is worth — so in some cases it is actually better to buy a new car rather than have it repaired.

Warning signs that a gearbox is playing up include strange noises, a burning smell, and vibration while selecting/changing gears. Most cars will show a warning light on the dashboard if the gearbox is faulty. If this happens, you should take your car to a mechanic right away. You can expect the cost of repairs to be upward of £1,000.

Head gasket: The most common cause of head gasket failure is an overheating engine. The signs that a vehicle’s head gasket has failed include a loss of power, overheating, oil contamination, external coolant or oil leaks, steam in the exhaust and, eventually, engine failure if a lot of water gets into the cylinders.

The cost of the head gasket itself is not that pricey, but the time and labour involved makes the total cost of the repair more expensive. On average, you could end up paying over £500.

Turbo: The most common reasons a turbo might fail include oil starvation, contamination or leakages. Regular oil and filter changes are important to prevent this from happening, but if smoke is released from the exhaust or the vehicle is burning excessive amounts of oil, these are warning signs something has gone wrong. If the turbo charger needs replacing you can expect to pay upwards of £1,000.

Clutch: Generally speaking, a vehicle’s clutch should last the lifetime of the vehicle without causing any trouble but certain driving habits, such as constantly riding or excessively slipping the clutch, can reduce its usable life. The signs that your clutch is not in proper working order include a high biting point, noise when pressing on the clutch, the clutch slipping and difficulty changing gears. Replacing it can be quite expensive and can vary greatly depending on the car, but it usually costs more than £400.

Dual mass flywheel: A dual mass flywheel is fitted to vehicles with a manual gearbox and is designed to minimise vibration and make the engine starting process and changing of gears smoother. Problems with the dual mass flywheel are often associated with clutch issues, but repairs tend to be more expensive, often costing more than double the price of a clutch replacement. These issues can go hand in hand, as a faulty clutch can damage the flywheel, and a failing flywheel can end up damaging the new clutch if it’s not replaced.

If you hear a loud rattling or knocking coming from the gearbox as the vehicle is idling in neutral, vibration through the clutch pedal, or have difficulty changing gear, you could have a faulty flywheel on your hands. You should take your car to a mechanic who can investigate the problem.

James Fairclough is CEO of AA Cars