When you tear down, I would recommend trashing most of the sand, or at least rinsing it out really well. The sand probably has some nasties in it that you don't want stirred up. You could keep a few cups to seed the new sand with.
Here's what I would do to move it..
1) Mix up as much new water as you will need for the move (too much is better than not enough...). If you're using new sand, rinse it well and have it ready to add.
2) Remove rocks to trash can or buckets with water. Make sure to put the ones with corals on top, or use separate containers for them. Try to avoid stirring up the sand.
3) Remove fish to bucket(s) with battery operated air pumps.
4) Remove as much water as you want to keep and then remove the sand (save a little to seed the new sand) and clean the tank out. You probably want to go ahead and scrape all the coralline off the walls for now. Rinse the sand if you want to keep it.
5) Move the tank, put in the new sand and seed it with a few cups of your old sand. Add the rocks and water as needed. Once you are done rock/coral-scaping, fill the tank up with water and acclimate the fish to the tank.
Hopefully some others will chime in with some other tips or better ideas....