OnMat offers self-service (ala cart) approach to pricing. You decide what modules you want to use instead of paying for a full product you don’t need. Simply download OnMat for free and turn on what modules you would like to use.
The Members Management and Integrated Billing are included in the base product for FREE for the first year excluding service fees charged by the credit card processor. Then a $99 annual membership fee paid on February 2nd if account has been onboard for over 6 months, otherwise the following year.