I had such a nasty time dealing with contractors I found in the phone book. Unfortunately, I struck out several times - with my first plumber, the electrician, the security system guy, etc. But my A/C guy, Emilio Medina, was a superstar!
Sears has a dirty secret they don't want you to know about. You walk into a Sears and tell them to install A/C in your house (or windows, or exterior panelling). They say OK and then charge you twice as much and then subcontract it to a local guy you could have found in the phone book. Medina is one of those subcontractors who installs for Sears. But we went direct to him.
He works with all the best brands - Carrier, Trane, etc. And unlike almost everybody else I worked with, he started and finished on the dates he said he would.