Thank you all for the awesome advice! We did talk to her teacher, and she said that a good digital with weighted keys & foot pedal would be fine to start, so I think we'll go that routh for now. I hadn't even thought of Craigslist to look for a piano - I just saw the ones at the piano store and got sticker shock. She also said that when we were ready she'd go with us to look at pianos and give us advice.

Thanks again, everyone!