Really fun game. 5 stars is hard to get but as long as you remember not to rush it isn't to hard.
If you make sure that when you get to a spot where you are making good money and can finish that star rating. wait and stock up on money.
100k to 200k with a 2-3 star rating will hold over pretty well.
I found that going up more than 10 floors in an elevator caused issues. Adding mini shaft next to the main one and breaking the main shaft off so people have to get off ever 6-7 solved all my problems. Basically just force people out of the elevator at certain points so it can head back down and stop the wait.