I bought a new house. The previous home owner had 4 dogs and wasn't using filters in his hvac registers, they lived there 10 years, who knows how long with the dogs. The coils have a nice mat of fur that I will be cleaning. Trying to figure out how to clean out the duct work. All I can find on Amazon are cheap kits for dryer vent cleaning or hvac cleaning kits that cost thousands. What would diy do?