substantially|notably} {high|very high|higher}, and {vary|differ} {depending on|depending upon|relying on} the {type of|kind of|sort of} the system. On {an average|a standard}, the {cost|expense|price} of {cordless|cord-free|wireless|cord-less} {business|company} phone systems {range|vary} from $800 to $1,500. The {number of|variety of|lot of} {channels|networks|stations}, transmission {frequency|regularity}, {security|safety|protection} {features|functions|attributes|components} and {other|various other} {facilities|centers} {determine|identify|figure out|establish} the {price|cost|rate} of {cordless|cord-free|wireless|cord-less} {business|company} phone systems.