If I add it up over the years and include keyboards I've sold or tossed or worn out?
Around $2000-2500 in Model M's - that's including M, M5-1, M5-2, M13's (some of which were bought new. Makes that number SCARY.)
Keytronic's got about $200 from me in their pockets - I used to use the FlexPro heavily and gave many to friends.
Focus, hell, easily another $300 since I had really, really bad luck with drops/spills/pets and those. REALLY bad luck. And I was paying $50/ea.
Chicony specifically probably has another $250 - think I was paying $50/ea for those and I know I bought 5.
Miscellaneous boards are probably another $750ish all said and done ranging from junkers for diagnostic work to PS2 keyboards that got broken.
Few recent purchases don't count since I got refunds, but add another $150 for a Ducky soon as it's on sale.
So call it somewhere north of $4,150 over the course of 23 years.
It doesn't get truly scary till you add keyboards I've gotten jobs to pay for. Goes right into the "oh my gods" territory.
3151's at list, HHKB Sun, SSKs, DEC LK461's, three or four SGI keyboards (SGI proto with IndyCam), $400 PC-Sun adapters, Sun Type4's at list, two Kinesis Advantages (original and Pro), two M13's at list, a couple M4-1's, and at least four ThinkPad-in-cases (various versions.) The total is probably north of $5,000 by the time you get through all the DEC/SGI/Sun alone.