So I was watching Ben Eater's videos on YouTube. (He makes things look easy which aren't necessarily easy.)
And I thought to myself, "self, he's got an itty bitty 6502-based computer there." And I thought: if I did that with a KERNAL + BASIC 2.0 EPROM, then I'd be halfway to a Commodore "sibling" computer. It would lack I/O, video, and sound, granted, but still, it'd be something.
Then I wondered: perhaps this is the kind of reasoning chain that made David think about actualizing a Dream Computer in the first place.
I see Ben's kit is $85, and doesn't include a clock, much less I/O and video and sound. So, I can well understand how the X16 could easily be $300.