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To back up, I started learning the Piano when I was 14ish. I started with Beyer and Schmitt. I think I finished half of the Beyer. I had a teacher for one year. I played roughly more than 30 minutes a day. It was good but then I stopped going to my teacher because lessons were boring. I played on my own for two years which was a very bad decision, I played a lot but random things that didn't make me a better piano player. I can play Fur Elise, Turkish Marsh and Moonlight Sonata Movement 1 well if that helps you guess my level. I started playing Moonlight Sonata Movement 3 but I'm stuck, I realized that my fingers are not strong enough so I started Hanon and it's great but I still haven't finished the very first one, I can't do faster than 100 (my left hand is weak!!!)
Now, for someone like me, do you have any book suggestions? I want to make my hands stronger and become a better piano player.
Thanks and sorry for the long letter, I just want you to know my background