Good idea on the PVC. There was also mention of a direct burial cable but I didn't spring for it yet as it was pretty expensive.
I see what you mean now. Private networks can have their own set of addresses.
Does this plan look ok?
Lake House NetGear Router: 192.168.20.x
192.168.20.1- Netgear router
192.168.20.108- Dahua NVR
192.168.20.x (any other devices via wifi)
Dahua NVR private network: 10.1.1.x
10.1.1.5- PTZ camera
10.1.1.6- IP Camera 1
10.1.1.7- IP Camera 2
10.1.1.8- IP Camera 3
Home Apple Extreme Wifi Router: 192.168.1.x
192.168.1.1- Home wifi Router
192.168.1.x (any other devices via wifi)
Yes.
I don't have a Dahua NVR but I am assuming the 10.1.1.x network is the default NVR private network so you would not need to specify a 10.1.1.x IP address to the Dahua NVR, basically the Dahua NVR must have at least one IP address on the same range as the cameras to talk to them.
The only slight drawback to the setup you are suggesting is that you would have no direct connectivity to the web interface of the cameras as they are on a different IP range to the main LAN and possibly segregated behind the Dahua NVR.
There are 2 possible ways I can think of getting direct web interface access to the cameras are; have a computer with 2 network cards one connected to the 192.168.20.x network and one connected to the 10.1.1.x network (if the two networks share no common infrastructure) connect the VPN remote control this computer and use it to access the cameras directly, or have the Netgear Router understand the 10.1.1.x network in addition to understanding the 192.168.20.x network, this would be vLan capabilities essentially. Ideally if the Netgear supports this you could set it up so that the camera network (10.1.1.x) would only be able to talk to the VPN and not the open internet.
The 192.168.20.x and the 10.1.1.x networks can both be on the same Ethernet switch, much like cars and trucks on the same freeway. 192.168.20.x devices would talk to each other but not talk to the 10.1.1.x devices and vice versa. Since the Netgear Router is a 192.168.20.x device it would not talk to any of the 10.1.1.x devices so the 10.1.1.x devices would not be able to access the Internet (which is probably a good thing with IP cameras, you generally don't want them talking to the Internet). If both networks were connected to the same Ethernet switch then they would have "common infrastructure" as mentioned above. With both networks on the same Ethernet switch the computer I mentioned above would only need 1 network card instead of 2. You could connect the 1 network card from the computer to the Ethernet switch and statically assign it an IP address for each network. For example you could assign the computer the IP address of 192.168.20.50 and assign it an additional IP address of 10.1.1.50. If you choose this option try to assign the IP addresses on both networks outside of their DHCP ranges. If the Netgear Router has a DHCP range of 192.168.20.100 to 192.168.20.250 then assign the computer an IP address of 192.168.20.99 or lower, or 192.168.20.251 or higher, same logic for the 10.1.1.x network which the Dahua NVR likely controls the DHCP range for that network.
One last warning if you are going to have common infrastructure (both networks, 1 physical Ethernet switch) is do not run 2 DHCP servers on the same physical network. If both the Dahua NVR acting as DHCP server for 10.1.1.x and the Netgear Router acting as the DHCP server for the 192.168.20.x network share the same physical network then 1 of 2 things happen; either one or both of the DHCP servers are smart enough to detect the presence of the other and stop working or complain of the others existence, of they are blissfully unaware of each other and give out DHCP assigned IP addresses as requested this means when you connect a device to that switch it could end up on the 192.168.20.x network or the 10.1.1.x network with no rhyme or reason, you could even have devices switching from one network to the other. Basically it would be bad to have 2 DHCP servers running on the same network.