I have a cheap Bontempi keyboard from the early 90s I think. Pretty whack, to be honest. 61 keys, no hammer action or velocity sensitivity. I want to learn it so I can write songs. It's easier to see how harmony lays out on a keyboard, and you can execute bass/chords and melody at the same time. I just want to get to a point where I can accurately execute ideas in my head for the bass/chords and melody in my left and right hand respectively. This would mean learning different rhythms in both hands. However, here's the kicker for me. Should I invest in an 88 key instrument, with graded hammer action, so it feels like a real acoustic piano, and learn from YouTube for free? Or stick with my current instrument and take one-to-one lessons?