I have set up Verizon 5g home internet, and getting good speeds close to the router. Since I have a four floor townhouse the coverage is poor on other floors even with the mini extender.
Can I set up a Netgear Orbi Mesh WiFi 6 system with the Verizon 5g home service? Any compatibility issues?
You should be able to run an Orbi just fine, but you'll need to use the Orbi in 'Wireless AP (Access Point)' mode instead of as a traditional router to avoid double NAT issues if you do any muliplayer gaming. (If you're not into gaming this might not be an issue) - If you set up a mesh network with Orbi, you'll probably want to disable the WiFi on the Verizon 5G Gateway and use Orbi to manage the WiFi and mesh instead, since I have found no way to register an Orbi as an AP / extender for the gateway.
Update for you... I actually added an Orbi AX6000 (RBK850) to my network with the 5G Home Internet Gateway. I ran into a ton of problems with the Orbi. Not sure if it was 5G coexistence stuff or what, but I ended up returning the Orbi after 2 weeks. The nice thing about the Orbi is that it has a 2.5Gbps WAN port so you can connect it to the verizon gateway and get >1Gbps speed to the orbi system... the downside is that Orbi is really glitchy (or at least it was for me) - Some of the issues I had: periodic internet unreachable even when wifi signals were good... ecobee and Lutron (IoT devices) unable to connect to the internet... issue with staying connected on an Android 10 tablet device.
The Orbi are nice hardware-wise, but the software needs work. If you want to add Access Points I'd recommend with going with something cheaper and more reliable. $700 for the 2-station (one router, one satellite) Orbi 850 is way too much for something with so many problems.