This may not be helpful to everyone, as it is a little more pointed towards mobile boutiques. People may be scared to open a door that they can’t see whats behind it and they may not want to shop somewhere that could lock them in. Keep the door open in your mobile boutique (or install in a permanent boutique if you don’t have a glass or screen door) and this will be the new door. It is clear so you can look in and out. It will also help keep the warm or cool air inside the boutique depending on the season, so you don’t have to worry about customers being uncomfortable.