Rookie's question -- just bought a pre-foreclosure house

[Rebecca Chen]

Just bought a pre-foreclosure house in the trustee sale. The trustee told me that I do have a temporary deed and the formal deed will be mailed to me within 2 weeks.  The house looks like nobody lives there (no furniture, empty). Can I go ahead and change lock on this house? If the answer is no, what kind of process I need to take before I change the lock? 

Let's say, if the house is obviously abandoned, can I change the lock and start renovation? 

Thanks a lot!