Hi all.

These are the manuals for the small boards we use to run remote installs.
https://pcengines.ch/pdf/apu4.pdf

Better details here
https://www.pcengines.ch/apu4c4.htm
You can even download the schematics there.

Price lists here
https://www.pcengines.ch/order.htm
As I said, these are cheaper than the netgate ones, that can be seen at
https://www.netgate.com/appliances

The "manual" for PFSense is here
https://docs.netgate.com/pfsense/en/latest/

And just for giggles, I checked their (netgate) support prices. Not too bad for a business.
https://www.netgate.com/support
And they have a pretty interesting service called "Zero to Ping" where "they will help get your Netgate appliance connected to the Internet and one client on the same network online."

Feel free to ask any questions, about either PFSense or the APU devices.
Roger