Are you licensed and insured, and can I see both? In Maryland, a home improvement contractor should carry a current MHIC license and liability insurance. A professional answers this instantly and in writing.
Who actually does the work, and who manages the job? Both crew models can work, but you deserve to know who will be in your house and who is accountable. At TrueCraft Contractors, one of the two owners manages every project.
Can I see an itemized estimate? Lump sums hide soft spots. Line items show you exactly what you're buying and make competing bids comparable.
What does the schedule look like, and what happens when it slips? Good contractors give you a start date, a finish date, and a communication rhythm. Great ones tell you honestly what could move those dates.
Ask for recent references, a written warranty, and how change orders are priced. Then trust the pattern: contractors who are organized in the sales conversation are usually organized on your job site, and the reverse is almost always true too.