Everyone has their own opinion... I personally have had a refurb D90 that I had to return and a refurb D7K that I had to return... Each time I got a refund and spent the money for NIB model.. I'd rather have peace of mind for my hard earned money.. Also, when you buy refurbished models, not every vendor selling will tell you what it was sent in for to begin with...
Regardless, if anyone is looking for a deal or wanted to point out price points they can PM the OP... I think there are way too many "price police" on duty... That goes for every forum... Rules almost always say something to the tune of "if you don't like the price, move on" but nothing ever happens when people say "we'll I can get it here for $200 cheaper so I'm gonna offer you $400 less"... Just a little rant... Didn't mean to stir the pot...
Members look out for each other here in the Buy and Sell forum, but there is no rule that says you can't specify that prices are high/low. As for your D90 and D7K, you bought them, had an issue, and returned them. Do you really think that you are just going to be able to "return" a camera you buy from a random person on the internet for a refund if you have an issue? Think about what you are saying for a second. You are recommending someone keep their used camera price, above the price of a factory refurbished camera with a warranty that if you have issues you can safely return.
$750 is reasonable for a camera that's had no issues and still under warranty so in this particular case you're still covered... More often than not, some people can't afford to take a loss that others could when re-selling gear... So will they try to recoup as much as they can out of it? Sure... Is it illegal? Not at all...
I just feel that if you like the price somewhere else then go buy it from there... If you want to suggest something to the seller then feel free to PM them... I just always thought of it as common courtesy... But then again thats just me... Sorry to get off track OP...