> Banning corporate ownership of single family homes, including forced sale of existing portfolios
Then corporate investors buy large buildings instead of single family homes (note that this is primarily what they do anyway), the prices for rentals in multi-unit buildings goes up (because it costs more to buy the property with more corporations bidding on it), the prices for single family home rentals goes up (because some of the landlords sell to occupants rather than smaller landlords so there are fewer rentals available) and what you've done is transfer some of the cost from more affluent prospective single family home buyers onto less affluent renters.
> occupancy requirements
They just convert unoccupied units to some other use or claim they're under construction, and if there is no exception for units under construction you've made construction more expensive and get less of it.
It's also kind of weird because they're already losing thousands of dollars a month in rent if the unit is empty, and the higher rents are the more they lose, so isn't the market already providing the incentive you're trying to get here? There's a reason well over 90% of the units in high demand areas are already occupied.
If you really want to increase occupancy then get rid of rent control -- it lowers that exact incentive to put the unit on the market which raises rents for all other units across the city, and has the same effect for new construction because of the risk (or certainty) that the building will be put under rent control in the future.
> mandated development on state-owned landed
The state often makes inefficient use of the land it owns, but it typically doesn't own that high a proportion of land in the city, especially if you're just going to use it to build more single family homes. Allowing a 100-unit building to be built where there is currently a single family home creates 99x more housing than converting some park to a single family home -- and then you lose the park.
> direct state construction vs. subsidies
Then the state uses government contractors who charge more and you get less construction for the same number of tax dollars.
And also, this is just a different kind of construction subsidy. You're not getting out of needing to build more housing.