GK Construction

You'll certainly want to ask them this. Steer clear of any company that is not insured in Pennsylvania, 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.

Many jobs in Pennsylvania will require municipal permits in order to be approved by the town's inspector. It's always good to ask who will be responsible for pulling those permits, and if you'll be expected to do it. You'll almost never be told to pull your own, but knowing that Jersey Shore Additions and Remodels permits are required makes you appear to be a well informed customer.

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.

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.