Best way to deploy DHCP server and foreman-proxy, then add to foreman?

I think I'm running into a chicken-and-egg problem here. I want to deploy
a new CentOS 7.1 server with Foreman, then install DHCP and foreman-proxy
on it and have it added as a foreman-proxy to our foreman server. This
will act as a DHCP proxy for another subnet.

Is there some way to assign a static IP address (also subnet mask, gateway,
etc) to a CentOS machine without creating the "subnet" first? Because the
foreman-proxy DHCP server will import that subnet.

You could use Foreman Bootdisk to install the host.

ยทยทยท -- Later, Lukas #lzap Zapletal

are there any other suggestions? I have not yet messed around with
bootdisk, so I don't know the learning curve / work involved at this time.