Good for you on getting them set up the right way.

Reptile thermostats are different then household thermostats. They are made specifically for controlling heating devices for reptiles. The cheapest model is the reptitemp 500r at about $25. The next step up is a digital thermostat from reptile basics. Either the Johnson controls or the ranco. Both are about the same. They cost $80. If you are willing to spend the money for the more expensive thermostat (which I recommend, especially if you plan on breeding) then order that and your flexwatt from reptile basics.

One foot of the 11" per tub should be fine. The flexwatt should cover 1/3 of the ground area of the tub. Wiring flexwatt is actually more simple than it looks. I did it myself and I know basically nothing about electricity and stuff.

As for housing them until you can get everything set up for them, divide the 55g in half with something. Do NOT secure it with tape though. They will find a way to get themselves stuck on it and it is not fun to get them off.

Get them each two identical tight fitting hides. Not those half logs, they are too open for ball pythons. They should have a small opening and the snake should fit in very snugly.

Heat lights are fine for a few weeks while you get everything together. But, please get some quality thermometers ASAP. The accurite seems to be the most popular. You can buy it at the home depot for around $11. It measures ambient temp, hot spot temp, and humidity so it is all you will ever need. Get one for each snake.