It seems that no matter how closely you scrutinise the small print of any document, there's always something to catch you out.

Take car insurance. If you're paying to guarantee your no-claims discount you might expect that, even if you have an accident, your premium won't go up.

You'd be wrong. That's exactly what happened to Working Lunch viewer Janet McKay.

She was unlucky enough to have three car accidents in one year - only one of which was her fault.

"I've been with the same company for 24 years so I guess over the years the no-claims built up," says Janet.

"Then a couple of years ago they wrote and called it a guaranteed no-claims discount, which I presumed meant I could make as many claims as I liked and it wouldn't affect my status with the no-claims."

So when her next premium from Eagle Star came through, she was surprised to see it had gone up from �660 to �935.

It transpired that her no-claims discount was the same, but her pre-discount premium had shot up because of the accidents.

SHUNTS & SCRAPES Average premium - �335 Number of claims - 4,230,800 Total cost - �7.08m Average claim cost - �1,673 More than 450,000 cars written off each year Source - Assn of British Insurers

"Most people do understand that a no-claims discount is exacly that - if you make no claims you get a discount," says Wendy May of Eagle Star.

"So I don't think that the term no-claims discount is necessarily that easy to misunderstand.

"I think where the misunderstanding came is that she did think this would also peg her premium."

But Janet's problem wasn't just with the small print.

She also felt that the company should have given her more warning that her premium was going up - the first she knew was when the payment demand came through.

"I think it's at the point you make the claim they should tell you the full implication the claim will make on your premium," says Janet.

Eagle Star say it's difficult for advisers to know exactly how much customers understand the insurance process when they're talking to them.

Confused

They will, however, take Janet's point on board.

"That's something we will look at, to try to make sure we mention it in the claims process," says Wendy May.

"If we think that our customers are still confused, then we will do something more to try and change that."

The company points out that Janet had done the right thing to guarantee her no-claims discount, otherwise after three accidents her premium would have been even more.

But her case is a good example of one of the principles of insurance - if you are making claims, your insurer will always reserve the right to increase your premiums.