My first lead but theres a propblem

[Miles White]

I finally have recieved a call back from a guy who is interested in selling his fathers estate, the only issue is the father owed 155,000 dollars in back mortgsge and I dont know how exactly to go about to make this deal happen or even if I should even consider taking this deal. the estate is worth more than what the back mortgage is owed and the average house has been sold for around 200,000 dollars. What steps should I take to make this deal happen?