Contract plugin needed

I need assistance in finding a plugin that will allow us to customize agreements from templates that we develop, on a per-user basis.

We need a method that allows a user to click “I agree” to a customized agreement that can happen QUICKLY and painlessly for the user.

If we ever need to go back and prove the written agreement between us and the user, we should be able to print out a pdf complete with their customized contract, date and time of ok click, and ip address.

Assistance in finding such a plugin or easier solution would be greatly appreciated.