Tier one did the install on the new units on our home. They were the company and units chosen by the builder. Ever since we purchased the home, we have had them out several times because the refrigerant was low in one or both of the units. The last time we were out, there was still not charge on the repairs and trip (even though we were outside of the 1 year initial warranty) because it was a recurring problem that started under the warranty. Sure enough, when we turned them on this year, the one unit was low on refrigerant again (after supposedly being fixed). I called Tier 1 out again, assuming nothing had changed as they apparently didn't really fix the problem last time. I certainly wish the person I scheduled the call with would have told me that this time it would be a $90 trip charge, plus another $185 to check for the leak. When the tech was here, he mentioned that if it was the coil that needed replacing (again) it would be approximately $1000. Completely didn't even bring up that the parts should still be under the manufacturer's 5 year warranty, just said that York doesn't reimburse them for anything anymore. Communication when I scheduled the appointment was poor at best. If I would have known their prices were so high, I would have called around. After calling around, I have found the going price is about $80-90 which include the trip and diagnostics/leak check. Shame on me for not asking, but shame on Tier 1 for not disclosing.