You don’t need to spend a fortune on a 2nd hive now, I would say $200 will give you a double brood boxes with 16 frames. Beekeeping is an expensive hobby as they need to be made solidly for durability. If you took into account the cost of this hobby, you shouldn’t have choosen the Flow hive style, it’s initially costly as we all knew that. You will spend more than just one hives down the track as you need more hives on standby to be able to run your colony efficiently.
Beekeeping is not about honey, it’s about how to manage a colony of insects that can deal with pest invasion themselves and with your manipulation, they can be honey productive. It also comes down to the seasonal weather, when it becomes too wet, too dry, too hot or too cold, the colony may struggle to make honey as they will eat them all or die out if we take away all their stores or without feeding them sugar syrup.
I lived in Canberra for a few years so I can understand how cold the winter is. With frost in Canberra winter, you will be surely need 2 boxes hive before the winter set in hence your 1st year will be spending most time to build up. The flow super is only be kicked in from Oct to Dec after you have a well established colony. After Xmas will be way too hot and dry for a good nectar flows for the bees to use the flow frames.
I suggest you watch Vinofarm YouTube by @VinoFarm to see his beekeeping experience, he spent 3 years to learn keeping bees before harvest a little or some honey this season.
I hope you won’t be that disappointed with a high expectation on the honey harvest since you invested so much on the flow hive but it is just a beginning of this hobby. I lost count of how many extra frames and boxes that I bought … I don’t see it will be yet done with it because beekeeping is addictive, one hive will lead to another and you will want more when your manipulation seem to work out so well.