What Is A Reasonable Offer?

In my shop, a "reasonable offer" would be asking for a discount of up to 40% off the price I list. So if something is listed at 50 dollars, I would sell it for as low as 30. A reasonable offer is NOT asking for anything below this. That is being a cheapskate here. If I have something listed at 40$ and you offer me 7$, it does not impress me. Poshmark also takes a percentage as well, and I pay out of pocket for all shipping discounts. Please understand.