Legal Question in Real Estate Law in New York

I suggest either that the co-borrower act as a guarantor (then not an owner but still responsible) or that, if the co-borrower has to be in title, you have a written agreement about how the property is to be operated, responsibilities for payment of mortgage and all costs (taxes, insurance, utilities, etc.) and what happens if someone dies. Without an agreement covering these things, if co-borrower is in title when he dies, his heirs inherit his interest.