You should check with your Department of State where you live on the permitted business types. For example, in NY engineering firms have to be PLLCs and not LLCs. Also, they cannot be Incs but PCs (professional corporations). I believe each state has their own rules. Then each business type has its own advantages which has been discussed at length in previous posts.
I realize that noone likes to hear this, but I would definitely say that it is worth the couple hundred dollars that it would cost to discuss this with a lawyer and/or accountant.
It depends on where you are, how you can incorporate.
AND
I would definitely consult both my lawyer and accountant.
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?
I'm corporate counsel for an international engineering company. I am also a Professional Engineer.
I want to repeat what the previous individuals have posted: Despite what you may have heard (through commercials), or your disinterest in paying an attorney, engage an attorney. There are MANY MANY MANY issues involved in establishing an engineering company. In fact you should interview possible attorneys before you select one...Have they worked with professional service companies before? Do they know the professional service acts that will govern the work you do? Do they understand all the various insurance issues associated with your type of business? Etc...There are many more questions that need to be addressed.