Although married people fax quite often, there are many single people who fax complete strangers everyday.
Faxing can be performed at any age, once they learn the correct procedure.
Certainly not, as far as we can see.
Yes, many people have no other outlet for their fax needs and must pay a 'professional' when their need to fax becomes too great.
Unless you are really sure of the one you are faxing, a cover sheet should be used to insure 'safe fax'.
Don't panic. Many people prematurely fax when they haven't faxed in a long time. Just start over, most people won't mind if you fax them again.
Being bi-faxual can be confusing, but as long as you use a cover with each one, you won't transmit anything you are not supposed to.