

I know in the US, local government, schools, universities, etc. will hold surplus sales when they get rid of old equipment. Maybe you can see if they do something similar near you?
You might also compare the price of a local system vs cloud hosting. That might work out to be cheaper.
Check the backplane before you buy drives or an HBA. The N3’s backplane just has SATA ports and molex power, you’d have to swap out the whole backplane and hack something together. The N1 and N2 are probably similar.