DHCP with 2 Servers and 2 Networks

I’m looking for help or documentation for setting up the following. We have a client that wants…

1) Two servers hosting seperate domains
2) Each domain on a separate subnet
3) Adding third subnet within year
4) Both networks able to see/ping each other
5) Possibility of each server as DHCP?

I’ve looked at having a subnet of 255.255.252.0 which means we could use 192.168.0.1 – 192.168.3.254.

Any help would be appreciated.