We are currently in a deep level "buyer's market" that is an indication that a buyer should NOT consider offering more than the asking price. A better way of phrasing this question would be, How much below the asking price should I offer?
You might want to consider contacting an agent to see what they could do for you. It won't cost you anything to meet and collect information and you just may pick up a few good ideas.
The "Eckler Team"