Further specifying "good": you really need a lawyer who's seriously experienced in these kinds of matters, not just any lawyer. It makes all the difference.
Also remember that there's a lot a lawyer can do for you in a situation like this, way before a lawsuit is even on the horizon.
Along with get a lawyer's opinion before doing anything i would stress that you can talk to multiple lawyers or firms to get different prices and opinions. Also I have found that people are usually happier if they find their lawyers through a connection rather than just searching Google or the yellow pages.
Also remember that there's a lot a lawyer can do for you in a situation like this, way before a lawsuit is even on the horizon.