Questions to Ask Before Hiring

I’m about to hire a drywall contractor for a couple of rooms, and I’m realizing I don’t really know what I should be asking upfront. Last time I hired someone for home work, I focused mostly on price and availability and kind of regretted it later. This time I want to do it smarter and avoid surprises halfway through the job. For those who’ve hired drywall contractors before, what questions actually helped you figure out if someone knew what they were doing?