I would tend to agree with less than 70-75% of market or book value. I do not agree with it having to do with the asking price.
I'm basing this in part taht there seems to be a trend that some Agoner's are of the opinion that something that is 2-3 years old with no warranty should still bring 75% or more of it's MSRP. You may find someone willing to do that but good luck. For the small amount of difference for what you can really buy something for if you look (usually not at MSRP) I would opt to go with a new unit than pay such a silly amount for a used piece. Just my honest opinion of course!
I'm basing this in part taht there seems to be a trend that some Agoner's are of the opinion that something that is 2-3 years old with no warranty should still bring 75% or more of it's MSRP. You may find someone willing to do that but good luck. For the small amount of difference for what you can really buy something for if you look (usually not at MSRP) I would opt to go with a new unit than pay such a silly amount for a used piece. Just my honest opinion of course!