Question:
Does sharia’ allow a woman to do door to door sales such as ADT, solar, etc.?
Answer:
As long as the interaction is restrained to the public space, i.e. the doorstep, there is no harm in sha Allah. Otherwise, even for men it is nearer to impermissibility because it is not known whether at any time illicit khalwa (seclusion with the opposite sex) will result. Add to that the danger involved when the salesperson that steps into a stranger’s house is a woman.
Hajj Gibril Haddad