Jason,
Personally, I would go BB with the new set ups. But, if you're intent on having sand, here is what I have done in the past moving a sandbed:
- make sure you have lots of NSW made up at the new place to replace water you will lose during the move. Scrubbing off hair algae and a good swishing in lower salinity water (say, 1.016 to 1.020) will remove detritus that has gathered in the crevices of your rock without harming your bacteria. Don't know how much LR you have, but be prepared for the scrubbing and swishing process to dirty your water quickly. When the water gets too dirty, dump it and start with more clean water.
- once you get the livestock out of the tank and put in buckets of tankwater, there should be 2"-3" of water left with the sandbed. Get a large rigid plastic spoon and stir up the sandbed. This will off-gas the anaerobic gases as well as loosen the detritus, leaving you with stinky filthy water
Move the sandbed to one side so you can siphon out the dirty water, then move the sandbed into pails for transport.
- your idea of cleaning the walls of the tank while empty is excellent. Some or all of the coralline and nuisance algae will die while the tank is dry. Cleaning it and rinsing it off will help prevent ammonia spikes from this dead stuff.
The rest of your plans sound good. Good luck with the move
