I bought when interest rates were just over 2% I think that was a good time. However, now isn't too pleasant. I did renegotiate recently and got .47% off woo, only for it to go up again .5% the next day ha ha. We are fine, we could've loaned a mil but took out nowhere near that as I knew things could take a poor turn eventually.
Perth way more affordable than most if not all the other major cities. However, still a bit insane. I wouldn't touch the market at the moment, see what interest rates and housing prices do over the next 6-12 months.
If you've got 20% deposit you'll get a loan no worries (edit: must say if you have a steady income that can show you can make the repayments). If you've got under you'll be paying a bit of LMI (lenders mortgage insurance I think that stands for). Having okay savings + steady permanent job really helps. I would say full time work (contract based) you'd have less luck depending on other financial factors.