Everyone makes mistakes. But when banks and lenders do it, it costs you money... big money.
"It's estimated each year in Australia alone there are $300-million in undetected bank mistakes" says Andrew.
One in every four complaints about the banks concerns transaction calculations. Mistakes made in working out your repayments for your most prized and expensive possession - your home.
"54% of monthly statements had errors. and 80% of those errors favoured the banks" says Andrew.
But now there's a computer program keeping the banks honest. It's called the Mortgage Watchdog and it analyses your mortgage statements finding miscalculations, minor errors everyday mistakes that cost you money.
"The first thing you do is put in the state and end date of each month, you put in the opening balance and here you put in the interest you paid for that period" explains Andrew.
Andrew Gray is the co-inventor of the Mortgage Watchdog. It takes about 10 minutes to enter the information into the programme but then barely two seconds to find out if the banks have made a mistake.
The programme looks at each month but Mortgage Watchdog suggests you look back over 4 years of statements to find any problems.
Most of the mistakes are of simple human error. A wrong number entered into the computer, a decimal place in the wrong spot. A computer glitch that misses a zero on an extra payment.
"I do like everybody else, trust the banks and I shouldn't have done that" says Jouko.
Jouko Hakola feared he was being overcharged. He used Mortgage Watchdog and found monthly errors were costing him dearly.
"Just monthly, there was an overcharge of 70, 80 dollars per month on the statements and I couldn't figure out why. Sure enough, $350 I believe I was overcharged."
A complete review of his accounts found his losses were greater than that - almost $1300.
"Look it varies, a few people find small problems, other people find large problems. When you show the banks they've done something wrong they're pretty happy to put it right" says Andrew.
Well perhaps not quite happy but Australian banks will do their own review of your accounts if you ask. The Banker's Association doesn't believe Australians need a program like Mortgage Watchdog because the banks do everything they can to get it right.
"We say to our customers, check four years of statements. If you don't find errors we'll give you your money back and we'll give you $250 for wasting your time. We know we're going to find errors."
For more information on the $198 program visit www.mortgagewatchdog.com.au