Do you mean the legal stuff to set up an office?
Not much in MA really...set yourself up as a DBA with the town or city you're in (unless you're going to be a LLC or Corp). Then send your DBA certificate in to the licensing board, with the names of your agents. There are no state laws (that I know of, I'm not a lawyer!) for operating a real estate business from your home. Obviously if you're going to have 25 agents coming in and out, that would be a different story. I'm assuming you're talking about a one person office with maybe some agents working from their homes.
If you're not sure, just call the licensing board...they are very helpful.