i've been using plex off of my gaming pc and an external hd and it's been great for watching movies at home so far. i'm reaching the limits of the external hd and would like to upgrade to some sort of bay with mirroring.

most extreme use case: two 4k streams at home and four 4k streams remotely

most common use case: one 4k stream at home and 2 or 3 1080p streams remotely

another issue is that i use a vpn on my gaming computer so i'd like to use something else as the dedicated machine so that my family can watch stuff and that i can listen to audiobooks while biking

what i'm thinking: should i get a mini pc to stream and transcribe with a cheap nas to host data? can i download from my pc on a vpn to the nas and then stream from the mini pc via that same nas? if i'm using the nas just for storage, do its specs really matter? for reference, i was thinking something like this mini pc with a synology 423

when it comes to networking, i really don't know what i'm doing and am happy to spend a little extra for something that will just work when i plug it in but i'd still like to keep everything around 500-1k before storage prices

thanks for the help. i hope i've provided enough information for feedback!

*edit: alternatively, should i just get a mini pc and a das? would i be able to download from my gaming pc directly to the das on a mini pc?