Marcio arrived on time and walked through the house with me explaining the process and counting the ducts and returns. He was professional and courteous. The entire process took about 5 hours and he showed me the before and after of the ducts. YUCK!! A thick layer of dust and residue was present everywhere. The after pictures were of clean aluminum. We had recently did a whole house renovation, so the duct cleaning was sorely needed. We will use Ductworks again!