However the cheapie keyboards without weighted keys will be pretty much useless, you won't make progress even in the beginning.
Hey. Don't you say that. I still don't have a good digital piano, I have been practicing in a cheapie keyboard, very small keys, non-sensitive, not weighted, 4 octaves, and I've been progressing.

It is not that difficult to do it on an accoustic (I've tried a good Steinway). The weight changes alot, but it's not hard to adapt. But at the start I almost can't ear a thing. lol
I've tried a Roland HP-101 and I think it's good, but not that good. It's much better than this damn keyboard (that isn't even mine), but I think the weight at the lower keys is the same at the higher keys and that the weight isn't high enough. When one should practice, I think one should practice at something with a heavy weight. Do you guys think that the difference between the HP-101 and HP-102 is very high? Do you think a Yamaha CLP-115 is better? Or is better a Yamaha CLP-150? Well, I will have to try them out.
Nuro, if you have access to a cheap keyboard right now, you should start practicing right now. You could start by chords, I guess.
Let us know when you buy something, and tell us about how things are progressing.

Bye for now,
OceanSoul.