Iowa Code
Chapter 552A - BUYING CLUB MEMBERSHIPS
Section 552A.4 - Limitation on membership period.

552A.4 Limitation on membership period.
A contract shall not be valid for a term longer than eighteen months from the date on which the contract is signed. However, a buying club may allow a member to convert the contract into a contract for a period longer than eighteen months after the member has been a member of the club for at least one year. The duration of the contract shall be clearly and conspicuously disclosed in the contract in boldface type of a minimum size of fourteen points.
93 Acts, ch 60, §4