Buying an occupied house at tax sale. Dealing with occupants

[Kenneth Soles]

Currently in the process of buying a house in Pennsylvania at a judicial tax sale through a county Tax Claim Bureau.  It looks to be occupied.  I've bought vacant properties through a judicial tax sale before but this is my first occupied property. 

Does anyone have any advice on how to approach the occupants?  I am a little hesitant to just knock on the door and introduce myself for who knows how they would react.   I want to come across as being willing to work with the occupant. I want to give them some time to find other living arrangements or even perhaps considering renting to them.  I am thinking about sending a carefully worded certified letter as my first attempt to contact them.  

If it ultimately comes down to me having to do  an eviction, ejectment or cash for keys then so be it.  If anyone could share some of their experiences, particularly on how they went about initially approaching the occupants I would greatly appreciate it!

Thanks!!