View their Website (if they have one) and see if they have listed their qualifications, other work they have done, experiances, and so forth. I agree with others, to a point. Independents may be an option if they are reffered to you as thier work has already been done and has satisfied the owner with the quality of their work. Google them and see how they are presentiing themselfs in other social networks. Here is an example. Review this if you may.
www.kalamazoohandymen.com