The spotlight is on rental property owners this tax time, as the Australian Taxation Office warns people to think twice before lodging a shifty claim.
Lack of paperwork backing up claims, careless capital expense claims, like buying new instead of repairing, and claiming the wrong amount of interest on loans are all on the ATO's radar.
ATO assistant commissioner Rob Thomson said it was also common for people to make mistakes due to bad advice.
"Rental property investments and taxation can get tricky, so it pays to get the right advice from the very beginning," he said.
"Don’t rely on things you hear at a Sunday afternoon barbecue."
The ATO estimates more than four in five rental property owners using a registered tax agent are still making errors on their tax returns, urging them to do their due diligence.
"Taxpayers are responsible for what they include in their tax return, even when using a registered tax agent," Mr Thomson said.
"If you don’t have sufficient records, you can’t claim it."
One of the dodgy tactics Mr Thomson sees is "double dipping" by reclaiming expenses that property managers have already completed.
"We sometimes see rental property owners ‘double dip’ on expenses that the property manager has arranged and included on the property’s income and expenses report for the year," he said.
The ATO crosschecks data from a number of sources such as banks, insurance companies and property managers to determine the accuracy of claims lodged, so it was not unusual for people to be slugged with a bill to correct mistakes.
"You need to keep detailed and complete records, including receipts, invoices and bank statements for interest expenses," Mr Thomson said.
"You should also detail how you calculate your deductions and any apportionments."
A number of resources are provided to assist taxpayers on the ATO website.