I find that a single implement or two out in front of a rural residence is the best way to buy an item. Course if there is no availability then one needs to go to a dealer and pay him his honest wages for finders fee, transportation, and some profit for him.
My last disc was a 3 pt (no tires to roll it home on) heavy duty, boxed frame, 6' disc in excellent condition, other than rust (big deal) for $400. I made no attempt to haggle (which I love to do) because I felt it was a good price and worth it. I had a tandem trailer and jury rigged it onto the trailer to get it home. Was a lucky find. Since I have retired and reduced my operation to the homestead, this fits right in with those plans and my current tractors with like sized wheelbases.
Another thing on that. I was driving on a road I seldom used and saw it sitting in the yard with FS sign. I continued to my destination and thought about it the whole time.....about an hour later I returned home and on the way stopped by and made the deal. My experience is you need to be ready if you come upon a good deal. To hesitate is to loose to another person who doesn't.
At a dealer it would probably run $700 at least and transportation would be extra.