Whilst redcliffe is a good club for twins your in trouble, they only have a twin commanche which isn't available for hire...at Archerfield Hempels and Sunland have Seneca's, FTA has a Baron and Partenavia and Duchy, and the aeroclub has a Duchy and a Part also.
Prices not sure, but none at cheap, well over $300 an hour plus landing fees + GST. FTAs Baron is over $400
afaik