1st that has money associated with it was a CP/M
(Quasar?) using a Televideo 910 terminal. And
then an S100 bus TurboDOS box. But
those were associated with my brother's business,
and the money was "token", so I don't think they
count.

The first "almost real job" was on a dual floppy
MAC as a bookstore. I helped them setup Peachtree
accounting. Got paid in books, mostly.

My 1st real job has me working on a Tandy Model-3
running TRS-DOS (tech support for communications
program called Teleterm) and then a Tandy 6000
running Xenix.

My PC on my desk was some type of Tandy PC, 8086.