A:Answer For the address space, you an assign pretty much 253 devices. e..g, 192.168.1.2 to 192.168.1.254
While the router only has 4 Ethernet ports, you can expand upon it by adding multiple switches. If you plan to scale things to a large number of wired devices, in addition to using local services which need a lot of throughput (e.g., a home server), then I recommend you go with more businesses oriented switches which offer many 1 gigabit ports, in addition to 2, 10 gigabit ports which you can use to connect the switches together, and avoid bottlenecks when multiple systems needs to access any servers that you may be hosting on the LAN.
If you need more flexibility with how you address each system, as well as support more devices with the DHCP, then you will need to either set up a separate DHCP server, or run a 3rd party firmware with a more robust DHCP server.
