To set up a networking system, you'll need to buy hardware and software and hire someone to set the network up. However, this can be done on a modest budget. However, you can construct a perfectly good server from any reasonably well-equipped personal computer. I've even made a decent server out of an abandoned Compaq 486 that I stuffed full of second-hand hard drives. You'll also need cabling to connect the computers to the hub.
Price varies, depending on the length of the cables.
However, you'll be comforted to know that the conductor is made of copper, not extruded gold. You'll also need a network operating system. You can also use equivalent systems such as Novell, Unix, or Linux products. The major expense in setting up a network is hiring someone to install it, which includes setting up a server, configuring each workstation, and installing the cabling and hubs. Hire a computer technician with proper training, certification, and experience.