Server Migration?

I have been using a DS1019+ for almost a year now as a family Plex server. After a while, I had to get an expansion unit. Both the Ds1019+ and the expansion unit are filled with 12TB hard drives so I am looking to upgrade the server. I am looking into building my own custom server and loading Xpenology onto it. The only issue is finding a case with enough hard drive bays ideally I am looking for something like 15 bays. My server rack has a short depth so it's roughly 20in deep or so. Is it possible to use 2 smaller rack-mounted cases with one system? I have looked at some SAN (fibre channel storage) cases that have lots of hard drive bays but I don't really understand them.

You could get a 1U RS1619xs+ from Synology and add an RX1217 expansion unit. But if you prefer to build your own thing then maybe consider Netstor NA381TB3 with a MAC mini inside and a RAID card.Either way, you can always use an SAS card to add additional rack units to your system.Here are the RAID cards: https://www.span.com/search/arc-18/5-And you can surely install Xpanology if you want to.I hope this helps.