I had North Valley out to my house last week to do a full inspection and cleaning of my A/C.
The technician spent a little over 2 hours at my house doing everything from going up in the attic to cleaning the unit outside. The technician was very knowledgeable and took the time to explain everything to me. For instance, I learned that every time a tech tests your refrigerant levels, they have to "steal" some in order to do the test. So every test is decreasing the amount and causing your system to run low. I had no idea! This company was very straight forward and honest.
I signed up for their annual service contract. It was one price and it covers 2 services per year. I am definitely going to have them out again to make sure the furnace is working at its best this winter.