#1 - every client gets their own VM. Unless it acts badly on my network, I'll install pretty much any requirement they ask me to on that VM.
#2 - if they require something specific in terms of hardware ("install this spyware directly on bare metal"), have the discussion about hardware setup cost/time and then expense them for the hardware you have to purchase.
Serendipitous to read this comment. I was just this morning trying to find a farm share to buy into. If (when!) you make your organic farming dream come true, register and sell on a place like this site: https://www.harvie.farm
Makes it easy for people like me to buy your stuff. Anyways, good luck!