Interview in Person
A reputable firm will come to visit the property before delivering a price. In some firms, the owner of the business does the project estimating and will therefore make the trip; other firms may choose to send one of their professional estimators.
Learn everything you can about the painter and his or her business.
How long have they been in the painting business? This is not the same question as "How long have you been painting?" You should ask both questions and know the answers. Someone who used to be an estimator may not have picked up a brush until recently. How did they learn how to paint? What is the quality level of their results? Someone who is self-taught likely does not approach the work in the same way as someone with 10 years in a painter's union.
Don't forget to verify insurance.
If someone is hurt on your property, your insurance will have to cover any expenses; if they become disabled, it can become very expensive. What if an inexperienced individual uses a heat gun and starts a fire? Always request a copy of their insurance certificate and be sure to review it. This is best done at the interviewing stage.
Check out their transportation.
Make it a point to see their transportation. Is it a company truck, clean and well maintained? This will tell you the company takes pride in their reputation.
Can they help you make the right decisions?
Find out what skills they bring to the table and what other help they could offer. For example, can they recommend colors? If you have employed a decorator, this step isn't necessary.
Questions or concerns of a legal nature should also be addressed.
For instance, what are their business practices if the relationship ends? Have they been part of any litigation associated with the business? Have they ever placed a lien on a customer's home? Why?