There are a few Ethernet options out there, it depends how you want to set the system up. The best are pretty expensive.
I have been impressed enough with Roon, to license it.
In terms of cost, there are 2 aspects.to consider,. Software licensing and hardware setup.
Roon software is $100 a year subscription. I find this cost quite reasonable, given what it brings to the table.
Hardware, you need .....
* Endpoints (ie: the Pi device etc)
* Rock server (Can be sourced cheaply, I got mine for $150)
* NAS storage (I already had it, but can be found cheap on gumtree)
I had a few.squeezebox devices, and they have been repurposed as Roon endpoints. So I can send my music all over the house. And every smart device in the house, can hook in and queue music, in any given room. I really love it.