Can you get a table like the ones that role under and over hospital beds? They adjust, have several different platforms to them etc. and are pretty damn sturdy. I’ve worked off of those tables out of hospitals! I believe you can buy things like that with FSA/HSA too! As far as really cheap goes, there are endless lap desk options, and since you plan to mount the monitors and would just need keyboard and mouse space, that could work!

Example one

Example two

Example three

I have something similar to the third one. Some days, I can’t tolerate sitting at my desk (I also WFH) the entire 8 hours because it triggers tachycardia/SVT, so I’ll ditch my monitors and take my laptop/mouse to the couch or bed and work off of it for a few hours/the remainder of my day.

Here’s another lying down desk example, and

here is an actual floor model that roles!