Adding a room or appt - who to talk to first?

[Marty Houghton]

Hi there!  

I'm looking to add a 3rd bedroom and/or a separate apartment in the garage of one of our rentals, but I'm nervous to talk to the city without advice.  Is there someone who can provide a rough outline for this process?  Should I speak with an attorney before hand?  Are there things I should ask or not ask while i'm there?

Thanks!

---Marty