digital signatures/paypal integration

(1) When an option is selected on a form, an agreement is generated. I need you to help me populate that agreement with information from the database. (2) I need digital signature functionality added to this agreement -give the user the ability to draw their signature. Any suggestions are welcome. My digital signature should be saved and automatically added to the agreement. (3) Once the agreement is signed, it should be saved for download the user and administrator. (4) I need the ability for digital signature for only the user when a few more documents are generated. (5) If the user does not sign the document, then we need a reminder mechanism - maybe email and maybe get link and give user ability to sign? Somehow signed via mobile phone? I'm not sure how these things work/ (6) integrate paypal to the site. (7) Upon certain answers to questions (which are stored in the db), you will help show some pdfs or add some documents to pdfs, etc