Phase 1)  Basic keyboard with a stand.  The keyboard should have weighted keys and be touch-sensitive. These features are important so the keyboard feels like an actual piano and not like a toy keyboard.

Phase 2) Digital piano console that looks very similar to an acoustic piano.   The Yamaha Clavinova has options to hook up to Apple products for fun things such as intuitive recording, karaoke, silent play through headphones, background bands, and Itunes sheet music conversion.

Phase 3) Acoustic Upright or Grand pianos provide musicians with the most power, the best touch, and sound.