There's different circumstances dude. I'm at 13c on my CrossCheck, and I'm estimating $2000 cost, which I'm pretty sure is an overestimate. Go read C&V, people pick perfectly-serviceable lugged steel bikes off curbs and dumpsters every day, or get them for well under $100 at garage sales. Not saying everybody that wants to can just do that, but lots of people do get lucky.
Not everybody needs/uses a light (so can be 0), but still they can be cheap. My light system cost me about $25 (zoomable-head Cree XML T-6 flashlight $8.98, pair of good 18650 batteries $15, two hose clamps $1). That also includes a road-found Cygolite Hotshot (free to me!), but before that I was using a $15 PlanetBike blinky, which was fine, so $40.
I am in a crime-free-enough suburbia that I use a pretty-cheap cable lock, it probably cost me less than $10. Enough to thwart a convenience thief is all I judged I need.
I bought a pair of Schwalbe Marathon Supreme 700x50s for $138.60, installed them at 5666mi on my odometer. They got something like 8 or 9000 miles before I replaced them with Mondials. The rear Mondial wore out (disappointingly quickly) so I put the better supreme back on, it's probably over 10000 miles by now.
Coupla chains, coupla pairs of brake pads. Coupla $15 helmets (Catlike Whisper knockoffs from fleabay). Coupla bucks for hardware to manufacture a
Kittier and decorate it with reflective tape.
If I had spent $100 on a sturdy 1980's Schwinn instead of
$1229.86 on building up my own CrossCheck, I'd be down in the nickel a mile neighborhood.