What is "low ball"


A lot of ads say something to the effect "no lowballers please". So I'm curious what people think is "lowball".

I'm looking for a percentage from people. I'm thinking less than 75% of asking price is where "low ball" kicks in, but I'm interested in what the general consensus is (if there is one).
jaxwired
Here's one for ya. How about a New D-35 Martin Guitar for 1700.00 free shipping and insurance, no paypal fees. Case, 3 sets of strings, Combo hygrometer therometer, combo tuner metronome also free.
I'm going to Wanted to Buy section. Maybe I find someone else willing to sell.
Is this lowballing or just the "Art of Negotiation"?

Guy: “If I gave you a million dollars, would you sleep with me?”

Girl: “A million dollars is a lot of money, and you don’t look that bad, so I guess I would consider it”

Guy: “Ok, since I don’t have a million dollars, would you sleep with me for $100?”

Girl: (outraged) “What kind of girl do you think I am?”

Guy: “We’ve already established the answer to that question. Now we’re just negotiating the price”