I vote second opinion as well. You have to be careful with these HVAC guys. There are some really good ones but I think some really take advantage of the fact that few people know anything about HVAC units, and also people are often captive customers when something goes wrong. I actually have recent experience with some HVAC issues. I had a routine spring checkup on my A/C, and also had the guy check my furnace while he was there because it was making a strange sound. He quoted me some huge numbers(see below), which I told him I would wait on especially since things were currently working. I intended to just research further and go from there, and I've actually done some of the work myself.
- Noise in furnace was due to inducer motor/fan going bad. Quoted $900. I researched and the part costs $140. Basically it's just a fan & motor that attaches to the furnace. Installation looks akin to replacing a bathroom ceiling fan, which I've done several times. Some basic electrical connections and attach to a vent. I ordered the part and will do it myself.
- A/C unit capacitor was old and needed replacement. $280. It does look old but was working fine. Part costs $20 and is literally just hooking a few wires to a metal cylinder and mounting it. I ordered the part and replaced it in about 10 minutes and kept the old one as backup.
- A/C unit contactor was old and needed replacement. $320. Part actually looks fine and was working fine. Part costs $20 and I've ordered and will replace when/if it goes bad.
- United needed 3 lbs of R22 freon. I believe him, he showed me his gauge and the unit's specs on the sticker. The issue is he quoted me $280/lb. I called around to a few places and they laughed at that price. Most were in the $150/lb range but I found someone at $70/lb. Getting it filled tomorrow.
It helped that my unit was working so there was no rush to do the work, but the point is you can save ALOT of money if you understand how to fix the simple components of your HVAC units yourself and shop around for the things you can't or don't want to do.