When are you moving and where are you? I'm sure you could drum up some support.
To add to what Chris said, use towels and lids over the large containter (rubbermaid) to keep the sloshing down and the water out of your car. Put the containers in lenghthwise (along width of car) as this will reduce sloshing, too. I pull all equipment first so the corals and fish aren't 'out of water' too long. Like Chris said, I drain some water first. Then I start pulling coral and putting them in one tub and rock in another. The fish can ride either with the coral or in a separate smaller bin. When you get to the new house, put the rock in first (unless replacing sand bed) so you can see how you want it stacked. Once the rock is kind of like you want it, start pumping water into the tank and let the discharge of the pump (or if manually, the bucket you are dumping from) go over/through rocks to reduce stirring up the sand bed. Plastic sheeting can help here, too (though I've never used it). Thens start loading the corals and fish back in. If it looks like there may be a slightly extended time frame between removing and getting the corals and fish back into the tank, run a power head and possibly a heater. That will buy you just about all the time you'd need. Don't plug the heater in until it is completely submerged, or it will crack and shock the crap out of anythign touching the water. This is probably the most common mistake I see made in moving.
Hope that helps.