I think the rooms should stay the same. Otherwise, a player could get to $20,000 in household funds and then sell off all the furniture to make $30,000. I just started a practice file, and once the doors had been removed (unfortunately you have to sell them rather than store them in inventory), a player will have $2,200 to work with. That should be plenty to start with, even after you've put all the doors back.
If you want to make it harder, you could have people do a money cheat to bring funds to 0 before you get rid of the doors (or even after).
One question I wanted clarified -- can you control all 3 sims until midnight of the first day?
Also, while waiting for them to get ravenous, my sims started getting skill points in video games autonomously. Do we have to add 30 points to those, or is it negligible enough -- and probably common enough -- that it's not a problem.