i have about 330 customers reccently i changed from trad to wfp.just to let them now about the changes i sent them a letter explaining how it's working and bla bla bla .also i offer carpet cleaning services and offered them a loyalty discount ,35% off for cleaning the carpets.already done one,booked another 2 and 1 needs to call me to arrange the date.and sent the letters out last friday.