There is an abundance of choice when it comes to buying second hand furniture in Melbourne. It can be done either online or offline, it is all still good. You can take your punt on op shops such as Vinnie's or even head onto eBay or Gumtree for quality second hand furniture items. Otherwise if you live in an apartment, no doubt you might come across postings with tear off slips with phone numbers and/or website details sticky taped up in the elevators or on the notice board as your walking to your apartment door; I mean there really aren't any excuses to say that it "is too hard to buy second hand furniture in Melbourne." It is hard work, yes like anything second hand: yet your rewards will pay off once you have gained some significant cost savings, and perhaps you can take yourself off the furniture rental treadmill once and for all.
If shopping online is your thing, a great source of second hand furniture is Nextag, otherwise there are many second hand shops in the Richmond, Kew and St Kilda areas; once again depending on what you are after. Also at certain times of the year, we all know that the retail industry goes on sale, so yes there are bargains which may mean that part or all of your pending furniture purchases need not be second hand, especially with sites such as Lifestyle Furniture available in Melbourne as well as whatsonsale and Johnny's Furniture.
If you are more of the feeling type, then it is more advisable for you to buy your furniture at a physical second hand furniture shop such as the Rabbit and Hares old furniture shop in Kew; twenty21 in Fitzroy, especially for decadent and classy coffee tables, and for designer second hand furniture, pardon the name: the bitch is back in St Kilda is worthy of your visit. It is important to find the time to find the right furniture for your domain; remember you need to live with it.