Quoted from snaroff:
I've purchased many high-end pins remotely (mostly on the East Coast of the USA). I've had great luck/experience. The key is getting great pictures. If you aren't that skilled at evaluating the pics, ask a pinhead friend for their opinion. It also helps to be skilled at interviewing the person selling you the machine. Usually not too difficult to determine if they are a serious collector that cares about the hobby or someone just looking to make a buck. It's a bonus if the person selling is also a Pinsider (so you can view their posting history).
Even if you weren't in Perth, it's hard to just deal locally. Good luck.
^^^What he said.
No problemo if you insist on a high-res picture link with dozens of pics showing the entire machine, ask enough questions including title-specific common wear areas, and buy from a known good-guy hobbyist.
If you're still unsure, find a local hobbyist to inspect the game for you (and send them a token of your appreciation for their trouble).
I've bought many long-distance games--no problemo if you stick to the above criteria.
Good luck with your purchase.