Hard to say, some stuff i already had, especially the drives i got over a longer period. But the rack itself was about 150 euros. I think some off the shelf racks would have been cheaper. But i also enjoy the building. And then the enclosures, power supply, elitedesk, etc another 200-300 euros.
The thinkcentre has a 1tb nvme ssd in it and runs immich and adguard and serves as a dhcp server.
The elitedesk is running truenas with jellyfin for now. Has a 120gb boot ssd, a 1tb nvme ssd, 4x 4tb drives (with an additional hot spare) for storage and a 12tb drive as a backup.
2 chieftec 3bay encolsures. Two enclosures and a sfx power supply fit nicely into the mini rack