Wordpress signup plugin

We need simple signup plugin for membership. Visitors to our WordPress blog have to be able to signup for our services (chosing from 1-3 price options), using form containing: - First and Last name; - Company name; - phone: - URL; - Adress; - email After signup system suppose to redirect them to PayPal so they pay for the membership, and return information about successful payment to our records. There are few Membership free plugins, but all of them are so complex and difficult to use. We need something simple without control of access to the webpages, post, etc. Modification of popular plugin is also discussable.