I had a girl try to pitch me a "carpet cleaning" deal including "one room cleaning done free". She could barely hide her attempt to scope out the inside of the house as I cracked the door. She didn't have any business cards or anything. After I got her to leave she got into an unmarked truck parked at the end of the block. Also, this was well after 9pm on a winter night. I now have a "no solicitor" sign. Haven't been bothered by crooks or missionaries since.