I dont answer the door unless my husband is home. I dont feel safe otherwise. Also we get so many men coming and half the time I am nursing, bathing or changing the baby. I started putting money in a pushka when people come (and I don't answer). So I am giving tzedakah anyways and this way I dont have to feel unsafe ao pressured while taking care of my baby.
I cannot agree with you (and other posters) more about the safety issue. Truly, you cannot always be sure who is legitimate or not. And I love the solution you came up with too!