I'm running a Fitlet2 J3455 https://fit-iot.com/web/products/fitlet2/. Small, fanless, low-power, runs cool, well-constructed. I bought the barebones model (currently $162). I have a 128GB M.2 SSD card, 8GB of RAM and the card with the extra two Intel Ethernet ports (for a total of 4) installed. When I bought them, those parts were about $40 each on Amazon. It has been running Opnsense for around a year with no problems. It provides network coverage for a two apartment house across three floors. The network is both wired and wireless. I have a 16 port switch and 3 Ubiquity APs using PoE. I haven't gotten round to setting up VLANs but that was the plan.
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