Example of my how I price things:
Double digit million gold items I usually do 1 mil under the current lowest market price listing. (So 12 mill item for 11 mil)
Single digit million gold items I'll do around 500k less. (so 5 mill for 4.5)
Under 1mil I'll usually do 100k less. (So 900k for 800k)
Under 500k, I'll usually do 50k less. (300k for 250k)
Generally I actually do even lower prices than that, but that's about how I'll price things.
The price I post my item at is the price I will sell it for, please do not send me PMs asking how low I will sell it for. If I wanted to haggle I would post in the exchange or add a bid to the item.
*There are some very few exceptions.