I note you are also looking at Motorhomes, May I suggest that you decide on what you really want to do - Buying RV's is pretty much like a pig making a Bacon sandwich - it is a big commitment that is usually done once.
Get some basic ideas by looking at www.caravancouncil.com.au/ where you can get free technical advice, ideas and checklists, that may assist you. Consider hiring RV's to ascertain the idea.
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Possum; AKA:- Ali El-Aziz Mohamed Gundawiathan
Sent from my imperial66 typewriter using carrier pigeon, message sticks and smoke signals.