The owner of the company called me up and briefly discussed my résumé. After a little bit of chit chat, he said where he was calling from and who he was and asked if I'd be available to come in for an interview the following week.
The next step was the in-person interview. The location was a warehouse in Brooklyn and everything was open concept. It was very a very casual environment. I met with the owner who was really nice and easy-going. He asked some questions about my background and how it applied to the advertised position. He then went into more detail about the company and its future plans. This lasted about 30 minutes. It went well and he wanted me to come in again the next week to meet the controller.
About a week later, I went in to meet with the controller. Interview was informal with the controller and the owner at the owner's desk. The controller was asking most of the questions and he asked some very detailed ones about accounting theory and how it applied to the job, the accounting software and theoretical questions about working in a start-up environment. This interview was more challenging and I had an uneasy vibe about the controller. He suggested that if I were to get an offer, I would need to start within a week in spite of the fact that it's standard practice to give a minimum of two weeks notice. In total, it lasted about 45 minutes and the opener asked me to call him the next day to discuss the next steps.