Not sure why they would feel their logo needs to contrain INC or LLC. A logo is not a legal representation of a business. When you design stationery, that is where you put the full legal name of the business below the address, etc. We've designed about 800 brands and maybe 1 or 2 has INC on it. Seriously, if they can't understand why Burger King or any large corporation doesnt have INC in their logo, even though their legal name is Apple, Inc. then they are really pretty ignorant.
As for the artwork, the only reason to be concerned about what your competitors are doing is if they are selling the same thing you are. If they are not, why do you care what they do, or how much they charge for it (or don't charge)? But not assigning a value to the design (which is really the most important part of the wrap) you put yourself on the same playing field as anyone who is selling vinyl by the pound or square footage.
Set your work apart with design work they can't get down the road, and people will pay a premium for it. But it's more than that - its also about educating them on why you're a premium vendor delivering a premium service. This involves much though on how you not only pitch, but present your work, and present your own brand. THose are all important in establishing your own brand promise, and value proposition which differs from those who perhaps compete in the same space.
And don't be afraid to have clients walk. You cant be all things to all people. Many here will say you collect the check and move on. It works for some, but I've built my business by doing the exact opposite. I seem to get more work by saying no, we won't do that and be associated with it. Thus, everything that leaves the office is at a certain standard, which represents the caliber of work we do, and more importantly, want to be associated with.
As for books, these are a few good ones:
http://www.amazon.com/The-Savvy-Des...F8&qid=1392950451&sr=8-3&keywords=jeff+fisher
http://www.amazon.com/Logo-Design-W...F8&qid=1392950566&sr=8-3&keywords=logo+design