(Not sure if this goes here? Sorry. )

At my college, a big issue in the music department is the lack of practice rooms (we're small in numbers but there are 6(?) for the entire department + non-majors who use them).

I've decided it's time to bite the bullet and shell out a few hundred for a keyboard but I'm kind of lost. I'm concentrating in education with voice as my primary instrument, so mostly I'd be using it to practice arias and reinforcement for my music theory/aural skills classes. Would I be missing anything too vital with a 76-key or should I just shell out for an 88-key?