Price is not a reliable indicator of quality. I had one of those Athenas, Cea. My MIL and I bought it new to share. It ran well for many years, and when I passed it on to someone, it was still running. I did replace the little rubber feed dogs.
I do love those thrift stores. I can get all the retail therapy I need at a cost that doesn't keep me awake at night, and I feel I'm contributing to some worthy cause - depending on which charity operates the shop. Some are worthier than others.
Now, as for the do-it-yourself brain surgery, having dealt with neurosurgeons during my youngest's infancy, I suspect you might do better. They misdiagnosed, performed surgery - or started to - then found it unnecessary. They still billed. I concluded from this that brain surgery is not rocket science.