PA upset tax sale questions

[Kesha Ferguson]

Hi all. We attended Westmoreland County's (Pennsylvania)upset tax sale in September to get a better understanding of what goes on and how properties are sold etc. We found a house on the list that did not sale and want to purchase it through a private sale. Does anyone know how that process works? Also, would it be too risky to contact the current owner to make a deal with them? We are quite interested in buying the house so much that we had a property search done to check for any other mortgages or liens and it showed to be clear. Thank you.