They guys came in and explained to me what they would be doing. They were here for about an hour and thirty minutes to two hours (2400sq ft). I was able to do what I needed to get done without interfering in their work. When they were finished they cleaned up after themselves with a vacuum and informed me about how dirty my air ducts and washer vent was. First time the air ducts had been cleaned since 2012. Definitely would recommend them and I will definitely use them again.