I'm an older (over 40 ) Electronics technician, & have found it hard to make a reasonable living at times, over the last 22+ years, but I literally have spent thousands, & thousands of hours "picking at" anything electronic, electric, & mechanical, that's worth learning, & repairable, over that time, & now, I can actually work on my own if I want. At times, I have had to.
Here's what I do: Repair three phase frequency drives, T.V., VCR, DVD, rear projection T.V., stereo, sun beds, computer, monitors, even rebuild battery packs for cell phones, camcorders, ac to dc power supplies, & laptops. Install ballasts for flourescent light systems, buy from E-Bay, sell built laptops, computers (desktops). Durabrand, Electrohome, Sansui, Prima, Advent, etc, etc. May not always get parts, or be worth repair, but the customer will ALWAYS come back. Also, sometimes "build" a test gadget for fellow Tech pals.
There's always something that nobody else with look at, especially if it's "picked at", by a non technician. You have to put way too much time into it to get back reasonable pay, but if you love it asa much as I do, you WILL make it work. I wouldn't give it up for anything, or anyone. I love it much more than the money. Rono.