Hi all,
while I'm quite an expert in all things 80s home keyboards

I am quite a newbie in arrangers. In fact, I have only stumbled upon arrangers yesterday, when I asked myself: How could I synchronize auto-accompaniments and rhythms of all these MIDI-less Casio keyboards, so that multitrack recordings get less painful, and live performances possible?
Now, as far as I understood, arrangers have this auto-accompaniment features with editable styles, which would allow me to program those Casio styles and play them with arbitrary chords, right? (And this is the main feature in which they differ from workstations, right?)
The next thing is to faithfully reproduce the original sounds, which could be done by multisampling the sounds. But this needs sampling features on the arranger keyboard, and my first research showed that these things start to get real expensive.
I know most of you guys will cringe at the picture of reducing an arranger to a "Multi-Casio" machines, but please: Could what I want be done as I described it? If so, could you recommend an arranger (or maybe other keyboard) that can do that which is not too expensive?
Another question: Can anyone think of an other (cheaper!) way of doing this? I know I could use a cheap sampler to play simple sounds, but I definitively want the auto-accompaniment feature. Is there maybe any MIDI device that can play predefined patterns based on chord key input?
So now you can start bashing me for this crazy idea. Come on, go ahead, I can take it. But I really would like to know what you think.