Your viable options depend on your intent.
Are you seeking an investment?
Are you seeking shelter?
Are you paying cash?
Are you buying with the money of someone else? (a common investor trick)
What is the situation of the subject property?
Or you can pond on the front door and ask, "Is this house for sale?"
They will ask, "How much you offering?"
You will start blabbering and the door will be slammed closed.
Identifying the portal of access will prove important to getting your offer heard. Knowing the area values will establish authority. Insight into their situation will get reception.
Some find the resources of a real estate professional invaluable in creating the correct message and offer for 'Off Market' real estate.
Best of success,
Annette Lawrence, Broker/Associate
Palm Harbor, FL