I have reached a point where there's nothing to do, have 3 girls maxed out, and nothing else happens, I even kept going until I went into negative money, being fired daily (3 times over already), is this a bug or the max rooms you can have is 3 per run in the current build?

stuck at the same point and wondering the same.

There's only 3 rooms at this point (6 characters, but you can only pick 3). Nothing else is in the game and since the next update looks like it's supposed to be the massively overhauled beta, this may as well be considered an early demo.