When you are ASKING ABOUT MONEY I think that you will not be able to buy one, but maybe I am wrong.
However, the GEM WK8 SE has by far the best sampler on board. It is unbelievable !!!
You can sample EVERYTHING and make a STYLE out of it.
For the rest? Every keyboard is good. There is no bad one. Depends on what you want.

Good PIANO SOUNDS? The 9000PRO is the best.
Wanna play around with a sequencer? PA-80.
Want to have the best designed styles with the most professional machine? Korg i30!
Etc etc. what you want is what you need. Not the other way around.

Ilija