AHHHHH! Bummer! I was looking forward to that tank! But it's better to wait, I agree - having just set up a 55g, I'd be terrified of the move. Plus it'll give you more time to do research and fine-tune your ideas. :)
If you DO set it up, you would definitely have to move it last, as stated in the PPs - but remember that you also just moved into a new house and won't be able to FIND anything for a week or two. Setting up the tank will have to be the first priority, but moving is stressful enough without all that! And I don't know about you, but when I've moved in the past, I tend to end up re-arranging furniture a few times before I get it right. Can't really move the tank around. You'll really want to be on top of monitoring for any toxins for the first week or so, and possibly have to do more than your normal amount of water changes. even if you manage to get everything moved and keep the beneficial bacteria living from point A to point B, you will most likely still have some fallout from stirring things up to such an extent. . . just not worth the risk if it isn't totally necessary!
I personally think that the best way to transport fish in a situation like this is in a bucket with a lid. They're gonna be stressed no matter what you do, but keeping them in a darkened environment will keep them calmer. I'd wrap the bucket in a blanket to keep the temp as stable as possible, and put a small heater (if needed) and an airstone in, so you can plug them up ASAP while setting up the tank. A bucket loses heat very quickly, and rapid temperature change is not a good thing - and I imagine that a bucket won't have the best airflow!
Yeah. . . wait for it. It'll be SO much cooler when it's all done and in a snazzy new place! Good luck on the apartment search. Moving can be such a nightmare, but it's also really exciting! Congratulations in advance on your awesome new apartment with the PERFECT spot for the soon-to-be GORGEOUS 55g tank! :)