We are currently in early stages of designing a new site for our training business. Our courses will take the form of joomla articles and we wish to restrict users access to only their relevant courses. In others words, we have 4 user groups and 4 article groups. Our main design considerations are as follows: we want to include paypal payment in the sign up / registration process. Can this be done? i.e withhold completion of registration until payment is recieved? we also want a good deal of control over our registration form - which is the best component for building thorough registration forms? As we run 4 main training courses we wish to have 4 registered user groups. In other words we wish to restrict user access to the course they sign up for. What is the best way of doing this? We're looking at the JUGA extension - is there a better way? Also, is it possible for a user to choose their own user group during the registration process? This needs to tie in to our article group / user group system Finally, we need a free affiliate program that tracks when an affiliate sends us a new user who completes the registration form. Which is the best, free affiliate program that suits our needs? Any help at all greatly appreciated. Thanks in advance