Apart from the flying and briefing costs, don't forget other things along the way. You will need to sit your RPL exam and depending on if your club/school can offer it, or you have to pay ASPLEQ to sit it, and Casa fee. Medical. ASIC. Will you get your own headset. ERSA, Charts, AIP or subscription to EFB. It all adds up.
For me it has been roughly $12K flying cost for RPL and about another $13k to PPL give or take. On top of that I would have spent another few thousand at least on good headset, charts, ERSA etc. And then given I have been at it for a few years, 3 ASIC renewal and 3 medical renewals at $200+ each etc.