Hi enid,
Nov is HOT HOT HOT....summer time beginning....i studied thr and whenever it reached Nov reminds me of S'pore....
As for hotel, any hotels in Perth City shd be ok but u shd try those serviced apartments along Swan River or Margaret River so as to enjoy the scenery which Perth is quite famous for.
As for places of interest, u must go Fremantle, North Bridge Rd, Chinatown, Perth City, King Park, Pinnacle and swan valley for those fantastic vineyard stay or to buy wine there.
As for extension to another city, just rent a car in Perth and drive up to Adelaide, Dawin and etc...on the way u can camp over at those camping site(FOC), horse riding, and etc.....but be careful don't hit any kangaroo as my friend's sister hit one and kanna fine AU$2000.
Hope this is helpful!