1. Credit scores don’t officially exist. There is no standard and each lender has their own way of looking at things.
2. The majority of credit reporting in Australia is ‘negative reporting’. You get enquires listed, and the ‘bad stuff’: defaults, judgments, etc.
There is a small amount of positive reporting, which is new and generally only accessible by banks - this is more up to date, and will show things like being behind on your credit card payments. However, fix up the late payment and you fix that part of the listing.
3. Your credit history is self cleaning. Credit defaults will fall off after 5 years, as will enquires. Serious credit infringements (also known as clearouts, such as where you go missing and cannot be found) fall off after 7 years.
4. There are multiple credit reporting agencies and they don’t ‘cross pollinate’. The three major ones are Equifax (formerly Veda), illion (formerly Dun & Bradstreet), and Experian.
5. You can get a free copy of your once every 12 months from each of these (also if you’re declined credit). Get these and check them. If you see anything incorrect, contact the lender to raise a complaint - which they must action.
6. Excessive enquiries look as bad as defaults. Anytime you apply for finance to someone who uses credit reporting (most lenders do) an enquire will be listed on your credit file with the credit reporting body(ies) searched. While it may save time to make 5 or 6 applications at once and pick one from the approvals, this will look bad to lenders who do searches over the next 5 years.
7. If you have defaults, get them dealt with. If you can, pay it off in full (this will change the default listing to paid). If you have to make a deal, do that next (this will change the default listing to settled, indicating the full amount wasn’t paid but the balance was forgiven). A default listing can only be removed by expiry of time, or if it was improperly placed. Some lenders will remove the listing if pushed - this is illegal under the a Privacy Act as it means the register is no longer a true record (but they will do it).
8. Who you make enquiries with can be just as important as anything else. For example, if your credit history shows enquiries made to small amount credit lenders (pejoratively called payday lenders) that is apparently used as a reason by some lenders to consider you a bad credit risk and decline the application.