What do you have against normal shops? Oh, you know, the shops that aren't hidden in the mountainous land of airport island? The ones that don't make you waste 25 minutes to see some robg hats that are 4 times the size of your character's head?(anyone else notice that?)
Not like It matters, but come on guys, there is plenty of empty buildings on era. You really want to make a secret entrance? The map of era is a labyrinth.