companies in your area. You can view their existing clients and see what kind of work they do. How long they have been established? How experienced are they? Read their testimonials. In the end it may come down to choosing the company you feel comfortable with. Here are a few suggestions of what to look out for:
Track record. What have they produced before? Can you see examples of work in a similar vain to yours? Where possible, talk to their clients in person. Every commission is different and requires a unique approach and feel. Out of the box solutions rarely work well in this creative industry.
The Producer. You need to establish a good working relationship with whoever is going to produce the video. Ensure this person will be on the shoot and in the edit and will not produce from behind a desk.