Things people wish they knew when starting in RE

Hello everyone this is my first post here on bigger pockets!

I’m 19 years old and I am currently going to school for a bachelors in finance. However my ultimate goal is to become a sophisticated investor with a focus in real estate. I’ve been taking the time to try and myself on all the ins and outs or real estate. Of course I started with rich dad poor dad, cash flow quadrant, think and grow rich, etc.

My question is what are some things i should know or perhaps you as an investor wish you knew when starting out in real estate.

Any insight would be greatly appreciated!