If you really don't have any other choice, then I would go with a keyboard, but I would get a plain upright or spinet first. For five years, before I got my grand, I had a digital piano, and I must say that the only thing they allow you to do is play the notes. You can't get a tone, or really very much dynamics, or phrasing, or even accents out of them. Mabe some of the new ones are better, but I played some last year, and wasn't impressed. So, in my opinion, the best "temporary" fix is to invest in an upright. You can compromise a bit. Little space, and relatively cheap, but still having real strings, and the action!
Anyway... That's my opinion!
Love,
Sarah