Don't use COIT; they take advantage of homeowners who are female and not handy. I live in Carmel Valley. Coit came to my house on Sept 7 to clean the dryer-vent. The technician gave estimate for $426, and told me it's a difficult job because the vent goes to the roof and he had to do some high-tech cleaning thoroughly and 3 times throught the "chimney," other wise it's a fire hazardz. And that recent there are a few houses in San Diego set on fire by the dryer vent not being cleaned.
It kind scared me a little. I thougth COIT is a reputable company, and agreed to the price. While he was setting up the tools and things, I went insidet to make some noodles. The technician called me in about 10-15 minutes to show me a pile of lint he extracted, and told me it's all done. I found out all he did was using a little brush hooked to a wire and used a drill to rotate through the vent pipe - no suction, no vacuming, no chimney cleaning. I asked him to try again, and another lump of lint came off just like that (see the picture). I was surprised and I showed him how it was done properly on youtube where people at least use a vacume to extract out the lint and dust while the brush rotated. He said Coit's vacume is too strong would damage my house. I asked to talk to a manager, the manager said I need to sign a waiver that if they damage my house they are not responsible....etc.etc... I didn't want to give the technician a hard time because he had to make a living, so I paide $426 for 15 minutes of poor job. The company is terrible taking advantage of people and hike the price and cheat on people with inferior services.
Long story short, it was extremely bad experience.