5. Adding Access Points ($30+ for AP and $10+ for Cabling)
Like the method just discussed, adding access points involves adding more APs to your network. This traditional method uses Ethernet cables to connect these additional APs back to your router.
Although this method may require a bit more physical work, it will probably be cheaper. Of course, you'll want to hide the cables somehow. If you have an unfinished basement or crawlspace, think about running the cable down there and drilling holes up through the floor.
You could also run the cabling through the attic and down into closets or walls. As with the powerline solution, you could use a spare AP or router in this solution, even if it is Wireless G.