Bought property in auction and tenant (if exists) not responding

[Constance Wong]

Hi all,
I just bought a property in San Francisco through an auction. The previous landlord (a management company hired by the bank) has left eviction notices on the door. We've been trying to contact the tenant by leaving notices on the door but no response. I would like to at least have an appraiser go in so that I can get cash out on the property. So my question is, can we enter the property after serving a notice of entry? If so, how long do I need to wait in case of no response?
Thanks a lot.