When looking at complaints, there's a trend the Better Business Bureau is seeing. It's good news and bad. Fewer mechanics are trying to outright scam you, but more just don't know what they are doing.

ou have a leak. The mechanic says it's the water pump. You get a new water pump and it's still leaking, so he says it's the radiator and replaces the radiator. You wouldn't have all the repairs if he diagnosed it right the first time," said Alan Bligh, Executive Director of the BBB Corpus Christi Office.

There are other situations where a well meaning mechanic could leave you digging into your pockets. According to the BBB, a reputable repairman should not begin any work on your vehicle until you have authorized that work to be done. The Bureau recommends you get any estimates in writing to avoid discrepancies. And, if changes are made to the original agreement, get those in writing too.

Bligh says some mechanics will not disclose hidden fees. These can include charges to reassemble or inspect the vehicle. Be sure to read the fine print if a shop advertises a free rental car or free towing. Usually this only applies if you use and pay for their services. If you decide to get the work done somewhere else, you'll be stuck with the rental or towing bill.

Once the work is done, how do you know for sure that the work was actually done and the parts repaired? "I

f you know what part they are replacing it could be kind of fun to etch something into the part. but always ask for the parts back," says Bligh.

For more information on auto repair scams, check out the BBB website at www.bbb.org.