Hey. We turned our basement in Bellevue into an office and guest room last year. Worked with New Day Construction on a Bellevue Home Remodeling project, and they handled the permits and inspections, which I really didn’t want to deal with. Moisture was our biggest worry, so they checked it first and added a proper vapor barrier before framing. Now I have a quiet office downstairs and my wife has her yoga space. Honestly, basements feel dark, so push for more lighting than you think you need. Egress requirements for any room used as a bedroom are a big deal too, ask about them early.
