In some other states, you can take possession of the property and have rights but you don't own it until after the redemption period is over or you've gotten the owner to sign off their interests by a quit claim.  

If he has "possession" of the property in many states it can take a legal action to get him out.

You should have a representative there during the access, to guard your client possessions, privacy.

After that it will be eviction for possession if she pushes it. 

If its been there for more than 10 years, then you are out of luck, the neighbor has adversely possessed it.

Each state has different laws around redemption periods, interest rates, and possession.

If an outgoing tenant releases possession of the property to you late you'll be unable to give the incoming tenants possession of the property on time.

As the beneficiary of the non-performing note, I would like to take possession of the property.

Which is how this type of deal goes down, the seller is agreeing to allow you to take possession of their property and pay their existing mortgage payments.

People argue that this type of transaction gets around issue 2, because the intermediary is the owner right before the final buyer takes possession.