Nissen Construction

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 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.

Always ask for references, and always check them. Keep in mind though that the only references you'll get are people who the contractor is certain will give him a good review. You'd also be well advised to check online review sources in Cambridge as well, which will give you a broader view of customer satisfaction for a given company.

Some companies may require a 10% deposit, some may not require any. For larger projects, you'll almost always need to give a deposit, and it's good to ask how much the deposit will be before going forward with a project. The Cambridge contractor will know how much they need for a deposit when they've given you the estimate, so ask early.