I’ve used this with much success (NanoPi r4s). It’s a mini board based off raspberry pi like system with an extra Ethernet out. It does not have Wi-Fi so you’d need to get an AP, but it’s swappable if you ever want to upgrade. With that and a switch for more Ethernet it’s fully open and customizable to put things like OpenWRT or whatever else you may want. Plenty of storage too.