As it happens, my roommate is a really, really excellent business lawyer. I get incredible service in exchange for washing the dishes! Of course, it helps that I did almost everything for a paralegal certificate a while ago, so I get to skip some steps in consultations.
(And I also have a lot of respect for people who can handle some of the, uh, personalities in the legal field, as that's what prompted me to do something else. Most people are great, but...) I have some family that I can lean on for accounting help, too. I agree that both are important.
I've had to pay taxes in more than one state often enough that I don't care to do it again (doesn't it seem like everyone wants to claim you as a resident, no matter how short a time span you spent there?), and if I'm not going to be in a state or doing much business there, I'd rather not register, though there certainly are some states that would claim you have to do so! The cost of being a foreign entity in multiple states can add up quickly, but I can see the benefit to a larger company or one that does enough business in a location that they might want any protections available to foreign entity companies in a state. I can also see why it would be important if you have employees in other states, too.