I've only ever used East Perth and all I have to say is 'do the right thing by them and they'll do the right thing by you'.

When ever I have to go over the pits I spend a considerable amount of time cleaning my car, both inside and out as well as under the bonnet (imo shows that you have a little respect for them), after that I check that all the basics are working i.e lights are all working, windscreen washer bottle is full and works efficiently as well as checking all over for any signs of rust and wear (when being pinged in my older cars).

I've never had any trouble at East Perth, though the main problem is due to them having only two pitts 'not sure about other pits', if you're not there by about 9-10am good luck getting anything sorted by early afternoon or on the day period 'this is mainly due to a lot of dealers loading up their teams with five, six cars in a row.

The guys at East Perth are the same since when I was going there from first getting my licence, now some of their kids are working there, no point spinning shit to them as they have heard it all before.

In short: Show some respect, present your vehicle respectfully and I'm sure you'll get over first time, and be let go if you have some minnor flaws (I know I have been)

Though when using East Perth: Just get there as early as possible or kiss your whole day goodbye.