Small yet powerful NAS. Runs very quiet.
Got it as Xmas gift and tried a for a week but didn't like it so it's almost new. I have updated to DSM7 Beta.

Current Amazon listing ($650 pre-tax).

https://www.amazon.com/Synology-DiskStation-DS920-Diskless-4-bay/dp/B087Z34F3R/ref=sr_1_1?crid=1RJKJOV2X9265&dchild=1&keywords=ds920%2B+nas&qid=1609732643&sprefix=ds920%2Caps%2C227&sr=8-1