Hello,
To be honest, I don't see reason to use entities, fields or bundles for that task. It would be overkill. It's just matter of saving exposed filters information in database. Then expose that data to use in views. For convenience I would also create two views for browsing that data - one for user, the other for admin. I could just display that data in table, but Views are way more flexible so I would use them whenever I can.
Second part of this project is sending information in emails. I would integrate this module with tokens to to make email content easy to adjust and change. And that's basically it. If you have questions, feel free to ask.
I am from Poland. I have great experience as Drupal developer - I specialize in creating and customizing websites to client's needs. I'm full stack front-end/back-end developer.
My experience and skills:
- highest completion rate on freelancer.com,
- over 100 A+++ ratings,
- over 5 years of experience in Drupal development,
- over 8 years in other fields (html, css, ajax, php, mysql),
- currently I'm building websites with Drupal, html5, css3, jQuery, twitter bootstrap, php ,mysql, also for mobile devices (responsive websites).
Regards, Darek