There is a whole class of people who are smart enough to fix simple things, but not smart enough to recognize their limited ability. They will strip out all the screws on the machine and then claim warranty after replacing random electronic components on the control board. In reality the problem will be a dirty contact that is a 5 minute fix.
In a world where people know less and less about how to solve problems themselves, I think repair skills are incredibly important for people to have.
Personally, I would happily pay more if you show me what you're doing and/or explain what I did wrong :)
And how did you build the skillset to do this as a side job if it wasn't by making the attempt yourself using available information and learning? Isn't your position just ladder-pulling that creates a population of less informed and less capable people?
Exploring the boundaries of one's own ability is not being "not smart enough." It's learning.