+1 on this idea, going to toss in my recommendation for an AMD 5600g second hand. Its basically a laptop CPU with built in GPU that handles my jellyfin transcoding without issue and has a super low idle power rating if you pair it with a quality, small PSU.

Does no one care about power consumption? Mechanical disks use, in my experience, 7-15w all day all the time just idling. If you live in a high energy cost area the ROI on going SSD can be as low as 3-4 years. If you can afford it, splurge for SSD. I spent ~$800 on two 8tb SSDs and I’m very happy with the choice.