I know the feeling. And frankly, I'm sure there's plenty of stuff that can't be fixed without propietary diagrams, etc.It’s just hard to believe the bad components can be found without sophisticated proprietary test equipment.
But I can never forget my a/c transformer breaking down in Spain a couple of years ago (and not due to over-voltage, as the thing was 220v-compatible). My friends took me to a back alley where this elder man from the Far East who hardly spoke any Spanish took out a multimeter and started measuring at various points.
He fixed a part which in the U.S. is a standard throw away and replace. Not saying the Kessy situation is exactly the same, as a Kessy is many orders of magnitude more complex than a simple power adapter, but goes to show in someplaces some people still fix stuff which over here is automatically thrown away without blinking twice.