Just as Terrence mentioned below, the best answer is "it depends". Zip code 15317 is split between Canonsburg (Canon McMillan school district) and McMurray (Peters Twp school district). The answer will depend on the school district, neighborhood, asking price and condition of the property, and also time on the market. If the property was listed within the past few weeks, owners are expecting close to asking price. If the property has been on the market for a longer period of time, sellers may be more negotiable.
If you are looking in a specific area, I will be happy to calculate the average sale price vs. asking price ratio. I can be reached via email at email@example.com.
Best wishes with your home search!
Julie Cain Cwynar
Howard Hanna Real Estate Services, Peters Township Office