Most places prohibit working on the electrical in a multi-family dwelling by the homeowner...depends on if your condos are standalone units or flats or townhouses. In my condo (a townhouse), it is illegal to do ANY plumbing or electrical work uniless you have a license. I could do work on my home if it was a standalone dwelling.
Even if it was against code, having a separate circuit for a bathroom is a good idea...plug in that hair dryer, curling iron, etc., and someone else turns on something in say a neighboring bedroom on the same circuit, and breakers or GFCI start tripping. Much better to confine it to the one room.
Important note - I'm not a pro
Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013
Now, I have no problem with the AHJ applying common sense in his enforcement and I don't agree with every part of the code. But there seems to be a glut of AHJs who are not endowed with common sense so it's good that they're limited to enforcing the code as its written and aren't given the latitude to do more.