We require you to come in an hour before busy time, and stay an hour after we close to clean, is that okay?

If you are available during these hours, tell the interviewer that you will happily come in an hour before busy time and stay an hour after close to help clean. It shows the interviewer that you are a team player and will do what it takes to ensure the team is successful.

If you are unable to work these extra hours, you will need to candidly share this with the interviewer understanding that you will likely not be considered for the job any longer.