Channel overlap isn't really an issue in 5GHz mode with DFS [1]. This also isn't completely accurate for 2.4GHz mode unless you will have high-bandwidth clients

Channel overlap isn't really an issue in 5GHz mode with DFS [1]. This also isn't completely accurate for 2.4GHz mode unless you will have high-bandwidth clients connected to multiple routers simultaneously. WiFi is cooperative by design, so it's possible to have 20-30 routers broadcasting networks in the same room on the same channel and a single client connecting to any single one of them at mostly full bandwidth. You can run into the Hidden Node Problem [2] if you have high bandwidth wireless users spread out and connected to multiple routers. With just two routers and a single laptop moving around an apartment, your biggest problem for signal (on a 2.4GHz network) will be the neighboring apartments and not the unused router, as it is just broadcasting beacon frames about every hundred milliseconds and not doing much else. [1] http://en.wikipedia.org/wiki/Channel_allocation_schemes#DCA_and_DFS http://en.wikipedia.org/wiki/Channel_allocation_schemes#DCA_... [2] http://en.wikipedia.org/wiki/Hidden_node_problem http://en.wikipedia.org/wiki/Hidden_node_problem