just sharing my experience.

i bought used 16TB hdds (HC550) like a year ago for 500 rm each. So far all are still functioning well.
They were used for chia mining by the seller, which to me means they were hardly abused (ontime was like 2 years with low writes).

maybe you can try looking for those rather than refurbished? Used HDDs are actually more reliable, provided they are used properly.
I gotten mine from Carousell and picked them up from the seller (so that there is no chance of postage issue)

haha... true... the chia price never really went anywhere.
plus from what I understand, for chia at least, the HDD were used to only store the plots...

SSD were the ones being destroyed by chia.