Almost half of Sydney's computer repair shops surveyed by ComputerCHOICE magazine are overcharging and incompetent.
The magazine surveyed 46 PC repairers by sending an anonymous shopper to each repairer asking for a quote to fix a broken PC.
According to the publication, the fault was minor, a wire disconnected from the hard drive and "the repairer had to open the computer to fully diagnose the problem".
The survey found that 48 percent of the repairers overcharged and made the customer wait for three days or more for a quote.
Two repairers permanently damaged the computer, then told the shopper that the fault already existed and suggested expensive repairs.
ComputerCHOICE editor Georgina Swan, said the results were "alarming".
"There's about a 28 percent chance your computer will not be repaired properly, based on our survey results," she said.
The good news was that about 26 percent of repairers fixed the problem quickly and didn't charge for the services, ComputerCHOICE said.
"They're the good guys of the industry. They go beyond the call of customer service. Unfortunately, their job is made all the more difficult by those repairers who don't do the right thing," Swan said.
Computer repairers can set themselves up as experts without any form of regulation or validation of their competence so it's important to be prepared in case something goes wrong, the publication said.
A spokesperson at the NSW Office of Fair Trading, said it had 30 complaints in NSW in relation to computer repairs and maintenance between 1 July 2003 and now.
To put this in perspective, there were 3955 complaints in NSW in relation to computer hardware and software products over the same period.
A further 296 complaints were in relation to defective goods over the period, Fair Trading said.
Commenting on the results, George Law, owner of Sydney-based reseller Bootstrap Computer Solutions, said some one- and two-man computer shops don't have the required technical expertise to service the customer properly.
Some "don't fully understand the technical aspects of a PC," he claimed. "The industry is like that anyway," he said, referring to the results.
He questioned whether IT industry regulation would make any difference. "How can it be regulated? It needs to be, but how?"
He added that some resellers are more interested in "up-selling the customer" and coercing them to buy a new PC rather than fixing what could be a minor problem with their existing machine.
"It could be a simple problem -- but they try to up-sell. Basically they'll try to sell them [the customer] a new computer [when] it's just a virus problem," he said.