1x Monitor is only acceptable for gaming in my opinion. I cannot believe people are working on 200$ screens. I mean you can also code on an 80 char terminal in theory, but why would you
Historically 16:10 monitors have had the same width as 16:9 ones (e.g. 1920×1200 vs 1920×1080) so there's no difference as far as having things side by side.
Regardless of that, if all you're doing is General Business™ then surely all you need to do is grab an all-in-one box, shove as much 3rd party ram in it as will fit & then nab a couple of monitors and an unbranded mechanical keyboard off amazon.
I did a lot of work on a £700(~$900) Optiplex with 16gb of ram and that was more than capable of running ubuntu on 3 monitors while being small enough to fit into a handbag