New Project Question: Requires User signup / edit listings

Hi there,

I'm considering using cms builder for a new project which is basically similar to a directory in concept.

1. I need to be able to have new users signup
2. Users will need to be able to login to edit their listing
3. If possible, need to be able to integrate with paypal to accept payments.

So my question is what add ons would I need to do this?

Would "User Sign Up Form" from the custom tools page be all that I need?

Many Thanks,
Jan