My BP is currently in a 36x18x18 tank, with a UTH on a thermostat and two lamps with 75W bulbs on a dimmer. Keeps it warm enough here in Calgary for her, though I do change out to 50W bulbs once it starts warming up outside

If no one has mentioned it, when you do get a thermostat, I'd make sure you get a proportional one instead of an on/off. They're pricier, but (in my opinion) safer for your snake, as the on/off variety simply allows your UTH to go full-bore, and then shuts it off once it gets to the designated temp. This results in temperature spikes and drops as opposed to a constant, sustained temperature

One thing to add to your list would be a cheap spray bottle (the Dollar Store ones work fine) for misting. Even with the cardboard/foil covers KMG suggested, you'll have trouble keeping the humidity up (at least in the winter) with 2 lamps.