For a long time I have said that taxpayers MUST keep a CGT record for every property they own. Even their own home. Because one day they may need the information. Even for your own home. Costs, dates etc...Even non-deductible expenses may be needed one day. A few recent ATO property audits have revealed a further concern and as a result we have updated our property CGT record keeping tool to now cater for how each property is financed and the source of all the funds used to purchase. Fail to keep this and they can disallow the interest deductions for one or many years. Or at least argue about it - Best to avoid that by keeping the right data from the start. Why ? The ATO will always want to trace all finance back to acquisition AND each refinance. Each loan, blended or not. So it makes sense to keep record of that. And file statements etc away. Hand the ATO your financing data and statements etc and the problem goes away. And the ATO want to see how the financed $$ was applied to the purchase. Our revised CGT record now does this. And the data guides what records to keep - Often for as much as 7 years AFTER the property is disposed of.