The "easy" way to do this would be to drop the mortgage interest tax deduction for mortgages under a certain % rate. It'll never happen, though, the US has been

The "easy" way to do this would be to drop the mortgage interest tax deduction for mortgages under a certain % rate. It'll never happen, though, the US has been artificially incentivizing single family home ownership since the 1910s. A better, and equally unpopular, way would be a land value tax at a rate high enough to discourage single family home ownership in high COL areas.