I'm a repair tech - hence made some assumptions that the author did not make.

Have done riveted keyboards on non-Mac machines before and would be surprised if an independent shop charged more than about $150 USD for it. It's not that hard to do.

You're right about the logic board being an extremely expensive fix, but it's also significantly less common than something like a keyboard, USB port, speaker or screen.

This is also something extremely Australian-specific, but consumer guarantees would probably cover any logic board damage within the first 1-3 years anyway, regardless of AppleCare warranty.