Unsure Of Which Way To Acquire Property:

Have a property that is family owned, looking to purchase from other family member. They currently are under land contract. What is the best option to acquire the property with no $ out of pocket except possibly cashing out equity to family member. ie-assume loan, wrap-around land contract, lease/option, etc. There is a balloon on the property in 4 years, which shouldn't be an issue. Ideas? Obviously want to make sure stay within legal aka on the upandup - routes Thanks for any help!