Being a red blooded male I agree that pretty girls can sell you product but, I have two points to make.
1/ If the person that answers the door wants to know details about the services you are offering, will the girls be capable of answering them? (for example... pricing, cleaning method etc)
2/ It's one thing to use pretty girls at organised events for marketing but you could be sending these girls to the door of a pervert or rapist, could you live with yourself if something happened to one of them?