NAS

Calculator

https://www.synology.com/en-global/support/RAID_calculator?drives=10%20TB%7C10%20TB%7C10%20TB%7C10%20TB&raid=SHR_1%7CSHR_2

https://www.synology.com/en-global/products/DS423+

https://www.synology.com/en-global/products/DS923+

HDD

https://www.reddit.com/r/synology/comments/z5asaz/nas_hard_drives/