Local network HiRes storage and player

Ease of use should be a prerequisite and anything less is not worth your time.  I started with a Mac mini server (fiddly), and moved to all-in-one server/streamer units by Antipodes and then Mojo Audio, and finally to my current sonicTransporter i9 (Gen 4) server and Sonore Signature Rendu SE Deluxe streamer.  Have you looked at the Small Green Computer website I recommended? 

My sonicTransporter i9 makes it very easy to rip and store CDs on the internal SSD, access music files from the SSD and from steaming services, and operate all functions remotely through my choice of my iPad, iPhone, or laptop.  In fairness, the Antipodes was also easy to operate but the newer models are quite a bit more expensive.  One advantage of using a separate server and streamer is being able to focus your budget on the streamer, which some believe has a larger sonic impact on your digital source.  One of the Sonore models, or the well-regarded Innuos PULSAR would be two streamer choices to investigate.

Don’t limit your options to what one dealer recommends.  Research the professional reviews and forum posts from owners.  Pay attention to the interface methods and options for streaming services and access/playback of stored music files.  Also, how stable is the company and how easy will it be to obtain quick, reliable support or service, if needed.  After all, the server is basically a computer and will eventually need updates/upgrades and possibly service.  When I was looking to upgrade my digital equipment a couple of years ago, the companies I looked at were Antipodes, Innuos, Small Green Computer, Sonore, Grimm and Auralic, but there are probably others.

For ease of use and excellent customer service I’d point you right to Innuos as their Sense app is widely regarded as the best streamer app out there for ease of use to the point where some owners have even ditched Roon, which says a lot.  Here are two nice used models you could try and if for some reason they didn’t work out you could sell them for little/no loss, which is nice.  A new similarly equipped Stream 1 or 3 will cost you a lot more.  Best of luck. 

https://www.usaudiomart.com/details/650246043-innuos-zen-mk-3-serverstreamer-with-2-tb-storage/

https://www.usaudiomart.com/details/650231817-innuos-zenith-mk3-1tb/

The issue is some of us like the Roon interface and can't be without it. I've looked at and/or tired the proprietary music apps, can't do without Roon at this point. In any case this beside the point for OP. For the ease OP requests he may just a well go for a streamer with on board storage, external storage makes things more complex.

Does roon actually make a noticeable improvement to the sound as claimed?

Small Green Computer NAS