before buying , make sure you get to try out the keyboards. You should be able to find something between $500-700 that should meet your needs. Find a music dealer that will allow you to sit down with the synth and play it..is it hard to program a pattern? set up arpeggitor? can it transpose via 1 button? keep it simple. You sound like you're looking for a performance synth that can add sounds to your compositions, so make sure it has easy features with the filters and effects. Hands on is most important,,once you find something user friendly, then shop the prices. good luck.