converting closet into 2nd bath

I've been told that any renovations involving plumbing or electrical you will need to get permits from the city as well as approval from the board.

#2 is correct, and even though it's "right next to the kitchen," it doesn't matter - if you're putting wet over dry, not all boards are thrilled with that unless you know for a fact that it's been done before in your specific coop.

What else do you need to know?

get an architect / drafter and a VERY good plumber. Also - just because there is plumbing (ie water) nearby doesn't mean you can put in a toilet, which needs to connect into the main WASTE line. Before you get too excited, you need to find out where that is (probably close to your other Bathroom) and see if that is your main option . . .

what about putting in a portable potty? you can pick it up and dump it down the faucet? or walk it across the hall to the other toilet? very convenient... better yet, take a dump in a diaper?

#5 lolololololol... i was thinking of that nasa lady....

OP - frankly, if i had the apt under yours, i would do everything I could to stop you from converting your closet into a bathroom. too many bad things can happen. if not right away, 5-10 years from now.