Edit post forms with password only

I have the gravity forms plugin installed on my site to allow users to write posts with pictures anonymously and it is working great. However, I would now like to allow these users to edit they're posts by entering only a password for that post, which they had entered in the original form submission, and access the form data for editing. I understand this will likely take a lot of heavy modifications and custom coding. Do you think this is something that is reasonably achievable with this plug-in? or are there any future updates that might make this easier? I realize I will most likely have to hire a professional web developer for this but any recommendations or insight on this would be much appreciated. Thanks for the great plugin guys, keep up the good work!

I'll try them, thank you.