I would not even attempt the Verizon wireless in Havasu at your house. I only get 1 bar of service and usually miss about 80% of the call at your house. Nextel has 3 to 4 bars at your house and most of Havasu. Verizon subleases use of a local provider and it is shetchy at best.
I don't know if Nextel has the wireless card but it would be a much better choice.
Probably the VoIP dealio I was telling we were talking about if and when they get the 25 mile WiFi site up.