AC work with no auth

[Katherine Walker]

First time poster, but I regularly listen to the podcast. 

Last week, I hired a reputable AC company to check on an outside AC unit that was cutting off repeatedly. Capacitor was bad and I authorized replacement. This week, the same unit wouldn’t turn on. Technician had tenant call me to tell me electrician would be needed as the unit wasn’t getting power but the breaker was fine - problem was somewhere in between. I then received a call from the tenant that the technician said to wait, he thinks he found a problem in attic. As it was the end of the day, I thought nothing of not getting a return call - figured it was something simple. 

Called the company office this AM and was told that a breaker was replaced in attic and then the condenser motor was replaced. I almost fell over when I asked the price and she stated it was $800+. I gave zero authorization for this and would not have proceeded without a second quote. I’ve been waiting on a response from the owner. 

Just received an email with invoice that says they gave me the discount as though I’m a vip customer - a $200ish discount, and that the owner will discuss with the employee. What recourse do I have on this? A $600 bill still seems very unreasonable for work I didn’t authorize.