ATTENTION /vp/
I got into the Lumiose city boutique.
All I did was....
>Battle all trainers in the allys
>Compete in the 2 star restaurant triple battle.
>Bought the berry juice from the store in question
>Played the Loto ID
>Entered every Cafe
>Took a tour of the Mueseum
>Worked at the hotel

After all that the Boutique let me into the shop. Female clothing downstairs, male clothing upstairs.
It is pretty pricy. Most items are at least 100,000 pokedollars.

Thought I'd share with those that still can't get in.
>You do need to restore power to the town to access all buildings and allys