1. Check for a permanent place of business, telephone number, tax ID number and contractors license. Also, make sure the contractor is properly licensed and bonded.
2. Insist on seeing copies of the contractor's liability insurance and worker's compensation.
3. Ask a potential contractor for customer references.
4. Insist on a written proposal and examine it for complete descriptions of the work to be done.
5. Have the contractor explain their quality control procedures and ask who will be supervising your project.
6. Read the contractors warranty information carefully.
7. The lowest bid may not always be your best option. Take all factors into consideration before choosing a contractor.