Hi Bev,
Please email the design/content and specificaions (as detailed as possible) that you have and we can provide a quote for the development cost.
Regarding the payments system, currently UltimateWB Full can be incorporated with PayPal. We can consider adding Stripe as a payment gateway too, if you are interested. Also, UltimateWB Full does have a membership system, and tickets/attendence system with calendar already built-in and customizable. But please provide your specifications so we can confirm.