I bought nest from Best buy and I watched a video and I installed the nest , the video did not clearly mention that I need to run C-Wire , it was end of last winter and the furnace worked fine , by the time my AC start working i notice almost every hour my AC suddenly shuts down and I did not know why, I happened to visit a friend of mine while Mr.Sal from JB integration was doing an installations for the nest at my friend house , I start asking him few questions and he told me right away i need to run the C-Wire to fix that issue , few days later he came to my house , run the wire and configured the nest the way it should be and since then I have no issue , I was lucky that I met Mr. Sal and he was able to fix the problem before anything happen to my AC , so yes it is an easy installations BUT you need to get an expert help to do proper installation , thank you Sal for the great service and for doubling my warranty you are my go to person from now and on and I highly recommend your service.