I was charged $200 to add 6 lbs of freon (R-410a) to my air conditioning.
I went to Amazon.com and 25 lbs cost $120 including shipping.
That should be approx $29 for 6 lbs of freon.
So labor which was 20 min, transportation, and equipment up-keep for John, the service person who came, was $171.
I feel that's somewhat unreasonable.
Just fair warning for the next customer.
Update: After listening to my complaint, the owner offered to refund my payment. That was quite reasonable of them. Therefore, I switch my review to 4 stars.