Best Thermostats Maintenance in Charlotte NC

Me and my property manager called separately to ask them to come out to our property to diagnose a compressor issue with one of our heat pumps. We were both quoted different prices over the phone - $95 and $130. Then two months after they came out they sent us a bill for $196. We called multiple times to multiple people. I left voicemails, sent emails to their service manager - Bobby, but was unable to get anyone on the phone to help or even discuss the issue. Poor customer service and much more expensive than others.