A survey suggests that garage charges are many times those of barristers. But don't despair, says James Ruppert

It's a good job I never used my law degree in anger. No snobbery intended, but if I had become a barrister, my hourly rate (£30) might look a bit feeble compared with that of the average main-agent garage mechanic (£100 plus). What Car? magazine's recent nationwide survey into garage labour rates confirmed the impression that they are very high indeed.

The survey also revealed that hourly rates vary across the country, from £49 for Vauxhall in Scotland to £140 for BMW in London. By contrast, it was found that unfranchised garages charge a more reasonable rate of £35 an hour across the UK.

Of course, mechanics do not pocket £100 every hour and go home £800 richer each day. They earn around £20,000 a year, while the rest (£172,000) belongs to their employers. This has lit the blue touch-paper as far as the Retail Motor Industry Federation (RMIF) is concerned. Its chief executive, Matthew Carrington, claims to be "mystified" as to why What Car? has appeared to mislead consumers in its survey.

Carrington makes the point that there is confusion as to whether this is a survey about salaries or labour-rates, as the piece makes the point that some mechanics would be earning more than a locum doctor, junior barrister or even a hack like me, if they took home what the garage charged for their services.

Actually, we know what What Car? is getting at, although Carrington also says: "Dealerships have high operational costs - they have to invest in training, technical equipment, substantial workshop premises, as well as customer benefits such as courtesy cars. There are also numerous costs associated with health and safety issues."

Quite right: there are overheads to consider and they have to be paid for. In that case, then, it is up to us to shop around. Because, if you have your car serviced at a main agent, you must be desperate, stupid, or maybe someone else is paying. Actually, that has been a major part of the problem, because main agents have been cushioned by the expense-account approach to car maintenance. Contract-hire fleets and companies build service and repair charges into the general running costs so, for example, the practice of charging for each litre of oil, rather than at a bulk rate, became commonplace. A company fleet might sign that expense off without a second glance, but a private motorist may balk.

It is no wonder, then, that once the warranty is up, many private buyers scurry to the relative safety of those in the independent garage sector, who need to be competitive to survive.

In theory we ought to be able to get our cars serviced at any garage, and indeed Carrington says: "A suitably equipped independent repairer, who has undergone the relevant training to meet the required manufacturer standards, can work on a vehicle without invalidating a warranty, giving consumers greater choice."

When the motor industry's exemption from EU competition rules ended in 2003, manufacturers could not limit access to technical information, training, tools or equipment.

However, "authorised repairer" status, whereby a manufacturer authorises an independent garage to service its vehicles, has failed to provide any real alternative. There were still only 100 of these garages when I spoke to the RMIF last year.

The trouble is that we are becoming more reliant on dealerships to repair our vehicles. What Car? noted that advances in technology have made simple jobs fiddly and time-consuming. Its survey indicated that replacing a main-beam bulb on an Audi A2 could cost as much as £66, with the bulb itself costing only £3.96.

Motorist Vince Chainey, who owns a new Renault Mégane but is also an enthusiastic classic car engineer, had similar trouble. "The bulb went and I thought it would be a simple job to replace it myself, but I couldn't see how to get to it. Eventually I took it to the dealer and they had to put the car on a ramp. It was the only way to get behind the bumper. I'm glad the car was still under warranty!"

Much has been made of the new British Standards Institute kitemark quality scheme, but after five months and fewer than 100 applications from the UK's 25,000 garages, only three have licences. So it is up to us to make sure we don't get overcharged or suffer inferior workmanship.

Calculating the cost of work is not difficult. There are manufacturer standard times for all procedures, whether it is unscrewing a bolt or a major crash repair. Most manufacturers' helplines will tell you what these times are, and then all you need to know is the garage's labour charge (this varies whether the garage is located in a remote district or SW1).

Multiply the figures and not only can you check their sums when you have the bill, but once you have a figure you can shop around locally for a better quote. Ensure that VAT and parts costs are included. And always remember to put what you want done in writing, with collection time and the minimum you agree to spend.

Most importantly, make it clear that you must authorise any additional work. It is not uncommon to be presented with a four-figure bill and a new engine because you insisted that the car be ready by 5pm. When it comes to the "can't get the parts" excuse, most garages have standard items in stock, but others can be delivered within 24 hours.

If it does all go wrong, what are your options? Talk to the service or garage manager straight away. If the problem cannot be resolved, you will still have to pay the disputed bill to get your car back. However, give the garage a letter detailing your complaint, saying that you are dissatisfied and that payment is made "without prejudice". This ensures the trader cannot say in court that you accepted the repair because you paid the bill. If the garage is an RMIF member there is an arbitration procedure.

So if you don't want to get ripped off, ask the price. If you don't like the sound of it, go somewhere else, or better still, sell your car and buy something cheaper, older and easier to look after.

Good garage guide

* Ask friends and relatives for recommendations

* Is the garage a member of a professional body?

* Ask the manufacturer for repair times and what should actually be serviced

* Tell the garage in writing exactly what it is that you want done

* Request that you be consulted about additional work

* Get quotes and second opinions from other garages

* Ask if workmanship and parts are guaranteed

* Check whether costs for labour, parts and VAT are all included

* Agree collection and payment arrangements

* Get a detailed invoice showing a breakdown of all parts and labour costs

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