You want a device, let's call it a BRoku, to route its traffic through your home IP even though it's actually physically located in someone else's house on their wifi network.
- BRoku connects over wired ethernet directly to a Raspberry Pi (3B+ or 4).
- Raspi connects to local wifi.
- Raspi's traffic is routed to a Tailscale exit node (potentially another Raspi) in your home LAN.