"As good as WiFi is, the spectrum is busy and will only get busier," says high-end AV installer Stephen R. Kraus. For the foreseeable future, wires will still distribute the best audio, video, and data signals throughout your home.

To avoid undue expense when you want to add new equipment, run bundled cabling, or at least a pair of CAT6 (Ethernet) cables through the walls while you're renovating.