Thanks for all the welcomes.
Actually the 10" dob seems like a good median between size and transportability. I can always make the ultimate decision when I go down and visit Andrews in Sydney, if the 10" is too big the 8" will have to do. The backyard problem can be sorted out too once I have something; if the backyard is no good I have a nice site not too far away by car. I can get my woodworking-wizard dad to help me build some form of transport box to help move it around (car is a 2001 SS Commodore so a 10" should fit in the back seat easy enough). The photography stuff can wait until Ive seen it all plenty of times myself.
I have an email from Andrews saying that the 8" is only $399 (website says $449), hopefully the 10" is less than the $799 it says on the website.
ps. I dont expect what ever I buy to be as good as the Celestron at the observatory, I meant if its half as good I will be more than happy!