Actually, we went to two local shops and she tried on everything they had, which wasn't much as far as women's boots go (basically one model from Vans, Burton, Salomon, and K2). The Salomon boots fit her the best, and I made her follow the steps outlined in the guide from this site. I should have mentioned that before. We bought all her gear from the local shop in one pop.
She's still a beginner and chaperones her schools 3-5 grade ski club. I'm pretty sure last year she hung out with the kids during their lessons. She knows what she's doing and just needs little pointers and a lot more practice. Upgrading from rental gear was leaps and bounds good for her because she actually said "whoa, I can actually carve with this board".
The most important part right now is to figure out how to keep her feet warm and in one place in the boot.