It sucks being in an apartment complex because there are always a bunch of unsecured networks floating around that the TV, or whatever, can connect to even if you don't manually do it.
Would using an older wifi router that you have lying around as a anti-smart device network work? Fire it up with no WAN signal. It's just a radio broadcasting an SSID that you can connect a device to. Are the "smart" devices smart enough to know there is no WAN signal and keep searching for a different connection, or will it be tricked into not being able to connect to the internet?
One option is to physically remove the WiFi card. I saw an article about this a while back, and it was a surprisingly simple mod.
On a related note, you should absolutely remove the cellular modem from your car as well.