best books to hit 2000 for a 1500 rated player

The problem is aptitude. People vary as to their strengths and abilities in Life including chess. I do not believe every 1500 can become 2000 regardless of time effort and money expended in that pursuit.
Endgames…..this is the area that most sub 2000 players neglect.
Imagine the dividends if you know how to convert 1 pawn/minor structural advantages into a win. likewise If you know how to “swindle” a draw from a player with a winning position but poor endgame technique.
Additionally your middlegame planning will be drastically improved if you know where you are heading….
1) Chess Endgames for Kids - Muller. My 12 year old daughters recommendation!
2) Silman's Complete Endgame Course - a good starting book.
3) Fundamental Chess Endings - get after Silman’s book
I can’t say whether it would give you 500 points! But mastering endings should see a massive jump in your performance and understanding on the game.
I was recommended How to Beat your Dad at Chess by Murray Chandler. Good for learners of all ages. Also, Play Like a Girl by Jennifer Shahade is very good, too.
Refining my suggestion of chess.com lessons. Look at Pawn Endings: Beginner to Expert. It’s 87 lessons…..I’ve decided I should take my own advice and have started on this!