I live in a maisonette too but have our own garden. Two of the rabbits live outside and I keep two indoors.
Rabbits adapt well going from outside to inside but its best to do it before the weather gets too cold so the temerature change won't be as drastic. Otherwise you'll be wearing lots of layers whilst you move the bunnies into the maisonette till they can slowly get used to the warmth of a house before being able to use the heating

. I don't bother caging my two at all, when we're in bed and when no one is home they are shut in the kitchen so they still have a whole room to move around in. Instead of having a "normal" door on the kitchen we took it off and made our own, just from a piece of wood and hinges from B&Q to make a half door so we can check on where they are before opening it in case they need to be kept shut in for any reason.
Make sure they have a litter tray in each room they're allowed in so they don't have to run as far when the need to pee gets them (I found mine are a bit like kids, they wait until the last minute then dive across the room to the tray). Lots of wooden toys are good to keep them busy as well, if your decorating before moving in I would suggest painted walls rather than wallpaper as bunnies take great pleasure in stripping wallpaper if your not careful.
Don't forget to make sure all wires are out of reach as well, go down on hands and knees, any wires you can reach bunnies will reach too. With the TV having the most wires for us (games consoles, Virgin box etc) we have a unit witch fits nicely into an alcove in our living room (one of those biggish units with shelves and cubboards around the TV space), the way it fits blocks all wires completely, that kind of thing is worth thinking about as an easy option for the bulk of wires you'll likely have.
Last thing, anything left on the floor, on the sofa, on low shelves, basically anything in bunny reach is property of bunny whether you like it or not.

My TV remote is missing half the buttons because it was left on the arm of a chair.