Half-price MoTs, servicing from just £50, free wiper blades with every service, free chicken wings with every MoT - on every high street, every van, every industrial estate, garages and dealers promote remarkably low car servicing prices.

But are these prices too good to be true?

In its continuing look at the service sector WhoCanFixMyCar.com, the comparison site for drivers looking to have their car repaired or serviced, built up a detailed picture of what price people are quoted for their service and what they actually pay.

1. The average final bill is £70 higher overall

"In analysing thousands of service and MoT quotes, a trend became clear," said Alex Rose, WhoCanFixMyCar.com marketing director. "While the average estimate is £150, the average final bill is £220 - some 46% higher. So, there you have it: don’t expect to pay what you were quoted. Right?

"Not so fast. While the price of an MoT may be fixed, the garage has no control over the condition of the vehicle being inspected, and no flexibility around pass criteria. A car coming in for a £25 MoT may pass first time, or require £1,000 of work to be allowed to leave again."

What happens when MoTs are excluded?

2. For ‘pure’ car servicing, the difference drops to as little as £17

"When the garage is more ‘in control’ of the work that’s required, the final bill is £44, or 30%, more than the price offered (£193 vs £149, on average).

"But what about the various ‘levels’ of servicing available? Well, for basic or ‘interim’ servicing, there’s just £17 in it. Or 17%, to be precise (£99 average estimate vs £116 final bill.) In our eyes, that’s pretty good value from our member garages.

What happens when the same logic is applied to the really cheap servicing prices (under £80)? Does the same pattern hold true?

3. Offers that are too cheap, are too cheap

When looking at all quotes for servicing for less than £80 (average: £68), the final bill was, in fact, 56% higher than the offered servicing price, at £106.

So, while a final bill that’s half as much again as the offer price might come as a shock to many, £106 is still far lower than the overall average service bill of £193. But, it’s important to note that this level of servicing will be far less comprehensive, often amounting to little more than replacement of essential fluids and filters.

4. A main dealer’s service pricing may be the most attractive of all

Most franchised dealerships are offering a servicing price that’s comparable to an independent or ‘fast fitter’ alternative.

"That said, drivers may believe that ‘the profit has to come from somewhere’, assuming that they will receive a higher final bill than they would elsewhere. The reality is somewhat different. While dealers’ quoted prices may be a little more, the average final bill is just 16% higher - a smaller jump than at other outlets."

Why do dealerships offer such competitive service pricing?

Simple: they see good-value servicing as a way to ‘bring drivers back in’ to the dealership, either for future repair work, or for a future car purchase, said Rose.

5. London prices are 20% higher than the UK average

Unsurprisingly, servicing is dearer in the capital. With an average final invoice of £232 for non-MoT servicing (vs £193 nationwide).

Meanwhile Scottish drivers pay £171 for the same work. Drivers in the north-west pay just £167 on average.

> How WhoCanFixMyCar.com works: 7,500 drivers describe the work that’s required on their car. In response, a network of 5,600 garages provides over 10,000 competitive local quotes, and drivers pick the garage they wish to work with, based on price, garage reviews, availability - whatever criteria matters most. Once the work is complete, drivers leave a review of the garage they’ve used including, should they wish, their final bill.