There is plenty of accomodation options around Melbourne, it just depends on your budget.
There is backpackers accomodation, caravan parks with cabins, budget hotels and camp grounds if you have your own camping gear.
Wotif.com usually has cheap deals.
Landing on the 11th is a good date as it's just after the Easter Holidays when everything is more expensive as half or Australia tries to take a break.
Not sure if you mean to store the crate for reuse when you leave or simply unpack it and abandon it at the airport?
Melbourne - Adelaide - Uluru - Great Central Road - Fremantle - Nullarbor - Adelaide - Melbourne in a $1000 Mini - May 2013. We did it!