Most informal interview in my career.
Process was not thorough enough resulting in a ton of confusion in terms of my technical ability to perform in line with the company requirements when deployed.
Because of the lack of the initial discussions and management being unable to determine if I'm a good fit for the role, the position ended prematurely. This was a complete muck around and disruption to my career because of incompetent management.
Be prepared to have your current financial position sized up when negotiating. Don't let them know what car you drive, if you have a mortgage, are married, have kids, or what your current / prior salary was.