I have to give it to the criminals, they are so good at spotting inefficiencies and weaknesses. This thief pretend to be a repair man and targeted churches and temples. He pretend to fix the air conditioner or water purifier and charged money. He was very detailed that not only he dressed like a repairman. He also had a card reader.
So the lesson?
Even if you are busy and even if the amount is small, make sure that you check the repairman who you have never seen. Be skeptical.