Hi yoavbo, I realise you didn't specify how you'll do the coast-to-coast from Perth to Sydney, but I just happen to have recently investigated Relocation rates for campervans. Apologies if I'm butting in and this is posted in the wrong forum but here are a bunch of links that might help. Keep in mind you may be able to do one sector at a time with different providers and/or use a standard rental car for some legs of the journey if there doesn't seem to be a reloc deal at the time. Personally, I'd recommend you drive the Great Ocean Road (Melbourne to Sydney) and also do Sydney up to the Gold Coast (or grab a cheap flight up there and drive the other direction - there are TONS of reloc specials from Cairns and Brisbane heading South, often $1 a day and often they give you free fuel as well). My guess is those two trips will cure you of a need to do road trips and the QLD/NSW one is definitely better than Perth to Adelaide. Anyway.

http://www.keenascampers.com.au/specials.html
http://www.ezitours.com.au/relocs.as...=ATN%20Listing
http://www.drivenow.com.au/onewayrentals.jspc
http://www.spaceshipsrentals.com.au/...rvan-specials/
http://www.coolabahmotorhomes.com.au/specials.asp
http://www.dingocar.com.au/VehicleSpecials.aspx
http://www.travellers-autobarn.com.a...location-deals
http://www.standbyrelocations.com/

Also if you have no luck with these and still want a camper, http://www.wickedcampers.com tend to do the cheapest "normal" prices. And get onto all their mailing lists as some companies don't update their sites too often.

~ Elisa (lurker extraordinaire!)