Buying into a partnership without an LLC

[Payton Law]

My partner owns a rental home with the mortgage in his name. I am going to pay him cash and will subsequently own 50% of the home. Will a lender allow my name to be added to the title without messing up the existing mortgage in his name? What all has to be done in order for me to able to claim my portion of the tax deductions?

In the future, we plan to form an LLC before acquiring any other properties and will deed this property to the LLC at that time if the lender will allow.