Wireless Vanguard. Cost alot but hardly work on Wireless

[rnorton888]

Anyone have a idea how to increase the range of the Vanguard cameras? I can get mine to work for about 40 feet. Would like to be able to use them at front and back of house without using wires to do it. Everything works. I have three if one is on the others turn off so its not like the others are overriding the one that is on and they are all set to the same channel. I also have a wifi but have them both set on opposite ends of the band.
Thanks
Randy