Scott's Air Conditioning & Heating, Inc.

This will be answered when you ask if all employees are licensed. The only way to obtain a legitimate tradesman's license is to be a legal or naturalized citizen of the US. The company may employ people in positions that don't require a license, however, so it's wise to inquire.

You'll certainly want to ask them this. Steer clear of any company that is not insured in Maryland, because that means that any incidental damage they may do on your property will be a real hassle to recover compensation for. It is never wise to work with uninsured tradesmen of any kind. Most states also require that someone have insurance in order to be issued a trade license. If they say they're licensed but not insured, they're being less than truthful.

These first two questions should only relate to services or good purchased directly from the service provider. Many products carry their own warranties, like roofing shingles or siding. It's useful to know what these warranties cover as well as how long they last. The "warranty agent" question is important, because often warranty agents work with the manufacturer to get you repairs under warranty at a much lower price.

This really only matters if you have a preference, but it is good to ask. If you have a strong ideological belief about unions or nonunions, it's perfectly acceptable to make a decision based on the preference.

Though a standard question, it's important to ask. Most contractors will tell you how long they expect the job to take without you asking. If they don't volunteer that information, be sure to ask. It's also helpful to ask if that's a hard finish date, meaning that it's the definite finish date. If it's a soft finish date, it may be extended for any number of reasons.