There is a seed bank in Australia im in Australia too ,led lights dont throw a heat signature like the high pressure sodium or metal halide lamps do they get warm but not really hot like the old days with HPS and MH you are probably going to need a 4ftx4ft tent to have more than 1 plant in it, there are 4ft x 5ft 2 room tents 1 part is 4ft x 4ft and there's another section on the end of tent for clones and mother plant that 4ft x1ft .
Im planning on buying one of them as a second grow .
Time of grow is dependent on how big you grow plants flowering will take roughly 9 weeks and add on how ever long you have it in vegetation for .
Tent should be fine in shed if you have neighbours fit a carbon filter on extraction fan .
Did I miss anything you wanted to know?