WT-5 alternative Wi-Fi solution for Nikon D4?

Is there an useable alterantive for the WT-5 for Nikon D4 cameras? The $700 price tag is to high for me.
I have found a few solutions but either they are not reliable or they require a third party wireless.
Is there cheaper solution so I can control a D4 remotely?
I have found a few solutions but either they are not reliable or they require a third party wireless.
Is there cheaper solution so I can control a D4 remotely?