i know my parents dont like people coming to the door uninvited they are both around 70 and it does say no canvessors cold callers but they still get some, if you need work, use fliers etc, other people seem to manage to get enough work without bothering and sometimes even frightning people by calling after dark, you may be well intentioned but im sure alot of your parents wouldnt like it as they get older, if you must do it please do it in daylight