L0 
L4: Noob This will probably take a little setup on your part then. I think to make this as simple and cheap as possible, and to isolate your validator from the rest of your network here’s what I would do.
Purchase a small router like the Protectli box I mentioned below. If they’re out of your budget then the Qotom Q330G4 is a cheaper alternative. If you go with Protectli they can install PFSense or OPNSense for you. If you go with a Qotom you’ll need to install PFSense or OPNSense on it. They’re both free. Once that’s done, connect the WAN port to one of the LAN ports on your main router. In the settings go in and put the new router in the DMZ. That puts it outside of your current routers firewall. Then plug your validator into the new router and configure ports, etc..
That way the validator is on it’s own network and all your PCs/Devices/Wifi are on their own. Isolated from each other. One thing for sure is to use static IPs and static ARP tables. OPNSense and PFSense make that easy, and they also have great intrusion detection software you can enable which will help to detect if you’ve been compromised.
