simple advice.. forget it.. no profit in it these dqays, the large operators have cornered the market.. to get the kit you will need to be able to cover even the basic models will set you back more than you will recoup in a year + I used to be involved but we quit a couple of years back because it just became completely uneconomic unless on a city wide scale.. we were taking phones to the big boys by the end because of how the networks and makers have ganged up against the customer and when we worked out the fuel costs there was no point.. we were LOSING money on each job!!!!