Javier represents Marcus, who's selling his rental property to Ben. Ben is represented by another real estate licensee, Francis. What is Ben's relationship to Javier?

Customer

Explanation:

A customer is a person that buys goods or services from another person, shop, business, organization, etc. with the aid of a financial transaction or other considerable.

A customer can also be defined as the receiver of goods and/or services from vendor, salesman/woman, etc. with the use of a medium of exchange like money or some other medium of exchange.

Cheers.