I believe it should be called heads or house instead of heads or tails when you flip a coin. Heads or tails doesn’t even make sense! There is no tail on a coin, but there is a building and while i know it is not a house I believe heads or house would be perfect because they both start with H and a house is a building so it is basically the same! Who even wants the “tail” aka the butt side of the coin anyways?