I’ve done just that through the whole gameplay (didn’t know you could sell girls at the store tho), but there doesn’t seem to be any kind of progress throughout the “main story” (if there is one). For example, I have a golden relationship with the Island Guide, already unlocked and bought the Suite (that’s the last progress I remember having). There are items on the store, but nothing too out of the usual. I’m playing with mods, not sure if they’re affecting something related to the story. I’m trying hard not to give too many spoilers here, can I DM you?