@Scot 's recommendation is correct, DocuSign would be a better route to achieve this. If you really want to do it custom, you'd likely have to enable user authentication, which would require creating and storing user credentials in your database. Then, when the user logs in using whatever authentication process you've implemented, they would use their authentication token to authorize the loan signature. This is not a fun thing to build (I know that because I'm building an authentication module right now). So, unless you have a database and server to handle this level of user security, a plugin like docusign is the best way to go. You dont want to put yourself at risk by having people sign things without being authenticated first.
This is a free tool, but has all the features that you find in a professional version. With Ultra Signatures you can quickly convert a PDF or Word document into gather electronic signatures, and share this document also. This has other features also, like Document Management, document merging, Workflow process, Custom Forms, the nice thing is it has a free version with all these features but there is a limit on how many documents you can use in a month.[/QUOTE]