where i learn power window repair?manuals?

[windshield]

yes i believe that auto glass replacement and power window repair are very hard to learn without practice on some shop with someone with good experience.i have some interest to learn power window repair.the same problem as to learn windshield replacement,i cant find tutorials for a good price.the only one thing i can find is a very expensive power window business franchise to learn the job.is an easy or very hard way to take the step alone with good electrical knowleadge,mechanic skill and some tools?thanks for the attention