Retirement tax questions

That absolutely did NOT happen to me!!! My documents were ready, but my accountant had her people tell me to file an extension, which I did, and I was asked to pre-pay so I sent them $500. They knew I owed over 20k for 2021 because they did my taxes that year!  I asked them to give me an idea of when they will be done, because we are expecting a huge return to apply towards that debt. They said the taxes will be done on time! We have to do business taxes first! That was in April. It's October 3rd and my CPA 'finished' them last week.  I needed to pay in full to see them, so I sent another $355. First thing I noticed was that an HVAC unit was depreciated out 39 years and $5,500 lower that what I paid!! And another HVAC unit was correctly depreciated to 5 years. She has been in possession of my taxes for almost six months and I found a mistake in five minutes. I know very little about taxes... She's supposed to be the best around.... 

Don't think for one second that the longer they have them, they better job they do...