That’s an insanely good price. I paid nearly that for my Mk1. If you buy and decide you don’t like it chances are you can actually make some money.
You’re looking for one machine that can do it all? That’d be Octa, but of course keep in mind it’s a sampler so you need to put sounds into it. If you want a machine that can make the sounds and do it all, that’d probably A4 or AR. I’m sure you can sample bass hits/chord hits/melody hits and put them on the AR if you fancy, that way your drum synthesis is deep. Or you can use the A4 for its drums, but then you’ll be left with one or two tracks for bass/melody.