Wallflower will have two Acts total. I can't guarantee anything on price, but it will likely be the same.
Quoting Rance below:
> As spoiler free as I can make it, Act 1 is it's own campaign with begining middle and end that will take you from LL0-5. Act 2 instead of taking the ending of act 1 goes down another path to continue the story.
> You don't need to own both to get a complete product or campaign, they just connect to one another.