You are house-sitting through a stormy week, and the doorbell will not stop. Every visitor gets inspected before you decide: look through the peephole, check the side window, ask questions over the intercom, compare them against the list of people you are expecting. Then OPEN or KEEP OUT before the candle that marks their patience burns down. Real visitors are welcome. Monsters in disguise are not, and each new night adds one more rule for telling them apart, from counting fingers to checking for a reflection in the porch puddle.
A door-inspection game for a stormy night. Most of the people at the door are exactly who they say they are. The rest are monsters doing their best impression of a person.
The first night starts simple: real people have five fingers, and anyone who says they are expected has to match the note on the fridge. Each night after that adds one more tell, such as a reflection that is missing from the porch puddle, a shadow that points the wrong way, or a knock that does not add up.
The rules stack up rather than replacing each other, so by the end of the week a single visitor can need several checks before you are sure.
Every visitor waits only as long as the candle by the door lasts. Inspecting is never free: each look through the peephole or question on the intercom spends some of that time.
Letting a monster in ends the night with a scare. Turning away three real people ends it too, so keeping everyone out is not a safe strategy.
Coins from a good night buy upgrades from a mail-order catalog, things like a guard cat, a salt line and a doorbell camera, plus decorations for the house. Finish the whole week and you are promoted, and the late shifts carry on from there.