How to Buy A Car – Know What You’re Getting Into

If you’re asking yourself which car one you should buy, our in-depth guide contains all the helpful advice you need to make a fully-informed decision

If you’re changing your car, the last thing you need is any expensive surprises. Fortunately, you can avoid this by doing your research before visiting a dealer, as well as knowing what questions to ask and how to act when on the forecourt too.

It helps to take our used car checklist with you, while having a firm idea of your budget and whether you need finance is also a great start. Yet, there’s much more to think about. In this guide, we look at what else you need to consider and how to choose a used car with confidence.


Once you’ve found a car you’re serious about buying, it’s a good idea to get an insurance quote before you sign on the dotted line. Most new cars receive an insurance group rating between 1 and 50, which insurance providers generally use to set premiums. This will give you an initial idea of cost. The lower the group rating, the lower the insurance should be.

Group rating takes into account factors including performance, image, price when new, price of parts and repair costs. A rating can differ between engine/trim variants of the same model, so it’s important to be aware of this when browsing. Your insurance quote will depend on the specific version and age of car you’re looking at.

Car Tax

For cars registered between 1 March 2001 and 31 March 2017, the annual rate of vehicle tax depends on which of 13 different bands its official CO2 figure falls into. For cars registered on or after 1 April 2017, you pay a rate based on the car’s CO2 emissions in the first year it’s registered. But from the second year there’s a flat rate, which is independent of CO2 -unless the car’s less than 5 years old, and had a list price of more than £40,000 when new.

For the eco-friendliest models, the annual rate of tax is £0 – nothing! Under older rules, cars with official CO2 emissions of 100g/km or lower (band A) were zero-rated for Vehicle Excise Duty (VED). Under the current scheme, however, only those cars with official CO2 emissions of Zero (electric vehicles) are zero-rated for VED.

CO2 emissions are directly linked to fuel consumption. You’ll pay less for a greener, more economical model than you will for a more performance-orientated one. Fuel economy has improved over the past decade too – with new guidelines designed to lower CO2 emissions across the board. So while you may think an older car is in a lower tax band, it may not be.

Fuel Choice

Diesel might have a reputation for being more economical, but diesel models can be more expensive to buy and the fuel is considerably more expensive at the pumps too. If you opt to buy a diesel car for its fuel economy alone, you’ll have to be a high mileage driver to get value for money. Diesel, especially the latest ‘Euro 6’ cleaner diesels, is still a great option for long-distance commuters. But needing to rack up the miles, to cover higher fuel and purchase costs, may be enough for urban drivers to look elsewhere.

It’s also well worth bearing in mind that diesel cars registered since 2009 – and many registered before – will have a Diesel Particulate Filter (DPF) installed in their exhaust. A car with a DPF isn’t suitable for town-based stop/start driving due to the risk of filter blocking. This is because it’s unlikely to achieve the conditions required for filter ‘regeneration’.

For urban use and shorter trips, you may well find petrol, hybrid or electric cars are much more cost-effective to run.

Fuel Consumption

Don’t take it for granted that your new car will deliver the fuel economy indicated by official figures. For cars registered before 2019, car manufacturers give 3 separate figures: Urban, Extra-Urban and Combined. This ‘combined’ figure should be a good indication of the fuel consumption you might get overall, but the official test is now so old that it’s become very poor at predicting real world fuel economy. In some cases, this can be up to 40% worse.

A new official test called the WLTP came in at the end of 2018, and this should produce official figures that are much more achievable in the real world.  From 2019 all official figures quoted for new cars will be the more reliable WLTP figures.


Check out the Euro NCAP safety rating of a car to see how well it’ll protect you and your family in a collision. Be careful when comparing ratings though. The test and star rating criteria have become a lot more demanding over the years, so you should really only compare cars of a similar age. You can view test results online.

If you have young children and you’re looking at family cars, it’s essential you can fit your child seat(s) in the model(s) you’re serious about.

Other Considerations

Practicalities – Are you planning to store your car in a garage? With vehicles getting bigger, be sure to double check dimensions. Not only that, it’s a good idea to take your kids on a test drive to make sure you can all comfortably fit in the car that’s caught your eye. Some dealers may even allow an overnight test depending on your circumstances.

Budget – It’s crucial to know how much you can afford and how you’ll pay for your new car. Will you use savings? Are you part-exchanging your existing car? Or do you need finance? Using AA Cars finance’s easy-to-use online tool, you can get a quote, check if you’re eligible and see how much you could receive – all without affecting your credit score.

Images courtesy of iStock.


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