You need at least one cable, with Internet connectivity. You can purchase any model of Unleashed product access points, and if within range, 4 Mesh APs can connect with your one cable connected Master Root AP. You may receive a router/DHCP server from your Internet provider, and can just connect your 5 APs on a switch with it, so they all get provisioned with Mesh enabled, and then you can move 4 of the APs to their desired location elsewhere in the building. If you don't receive a router with your ISP connection, you can choose one AP to be Master AP in router mode, to provide DHCP and def-gw for your network, with 4 Mesh APs.
Unleashed is designed for simple SMB (up to 25 APs) useage with router/DHCP role if needed. I hope this is helpful.