Laptop gaming computers can range anywhere from hundreds of dollars to thousands of dollars. If you want an average gaming laptop computer, then you should probably pay $800 for it.
Your question is pretty general; that is, you have not specified what type of repair.
Computer repair generally is charged by the hour. A consultant that works independently (not for a company) may...
This really depends on many factors. 1) Where you are located? 2) What you want to be taught? 3) Who do you want to teach you?
If you'll answer these questions I can give you a better answer.