The store is amazing it has tons of details and is a great design a suggestion i have is maybe dim down the lighting in room (third and fourth picture)
Try adding some decal textures from the ROBLOX library, as it could bring out more realism features to your clothing store! I am stating this because I am not to fond with the texture of your water fountain, it seems to bores me to see how unoriginal it is.
Here are some tips on how to making your building a little bit more interesting:
I dislike the terrain outside, and how you have a waiting room styled entrance. Mostly everything in the build is a free model, so I suggest tagging each model, before saying it’s “your build.” Overall, good job!