Amount lent, interest, monthly payment, maturity date, and any other specific details that pertain to your agreement.You should also sign a mortgage, or deed of trust, depending on your state to secure your lenders money with the asset.

Can someone share with me their experiences pertaining to balloon loans/terms?  

It's always good to have an attorney you can refer too because wholesaling can borderline some real estate laws and regulations pertaining to your particular state.