I'd hate to guess what I've got in tools & boxes. Also well over that $20K mark. Specialty Porsche/Lotus/Alfa tools alone would be in the $2~3K range. Craftsman "legacy" hand-tools from the late '60's, three generations of other stuff. Proto, Snap-On, MAC, & others since the mid-'70's. One drawer alone full of taps and dies. Three Snap-On roll cabs, one is bigger than my refrigerator, with a side box. Other two are 32"Wx38"Hx18"D.
Not sure someone starting out could afford to buy the stuff I've got unless they could come up with enough cash. But I have seen newly minted Tech School folks go into heavy debt to finance BIG roll cabs from the various vendors (some even with sound systems built in!). "Indentured servitude" would describe those kids. The dealerships and shops aren't paying a 50/50 split, guaranteed. More likely a flat-rate scheme with an agreed-upon hourly stipend. The diagnostic computer tells 'em what bits to swap out, with mechanical expertise as a secondary consideration.
My former partner and pal recently watched a dealership "newbie" climb into a mid-nineties Ford van and couldn't figure out how to start it... couldn't find "The Button"!!