A year ago I had a "major HVAC company" do a repair on my A/C - the system was struggling ever since, and they told me it needed replacement. At the beginning of this year, Bell Cow came out and for the price of the service call had it up and running in 10 minutes - the new capacitor from last summer had been wired incorrectly and also had a broken lead wire anyway. Fantastic and proven honest with that call - they could have soaked me for a new system.