This is a very interesting situation that happened to us recently! It can be a ticklish situation. Check it out!
So you were the high bidder at the foreclosure sale ... your work is just beginning. You don't know what condition the home will be in until you get in the house, but the owner or tenant is still living there. What do you do?
The best thing you can do is to work with them. Understand their situation - many think they are doing a workout with their bank and the sale is a "surprise" to them. If you listen to their story, and offer them the home back you will start to get somewhere. Usually, they won't want the home back. Either they can't afford it or the memories are too negative.
They might want to rent it for awhile while your sort out your deed and marketing plan. If they keep it up and move out nicely this can be a good thing for you. You can even have them stay there rent free if they take care of it and don't strip it on the way out.
The easiest is to give them something for moving. We just experienced one where the owner had a list of things he had done to the house. It included new dishwasher, cabinets in the garage, window blinds, etc. The list included many items were know as fixtures, but they were of value to the owner. The list totaled over $3,000. He was emotionally done with the house, however, and wanted to get on with his life. He took $1,800, will be gone in 10 days, and is watering and mowing the place. A win/win for the investor and the owner that just lost his house. It is making the best out of a bad situation.