The cost of a "pied-à-terre" ranges from $500k to over $1.5m.

A new house costs at MINIMUM $400k to build (in New York state, not to mention the city).

There are around 100k pied-à-terre in New York CITY alone.

There are about 350k homeless people in New York city.

Taxing all of those secondary 'homes' at 40k would and spending those taxes ONLY on new housing construction would yield at MOST 100k houses (per year).

So I was incorrect in what was more efficient IF taxes only go to building new houses... which I AFAIK is not accurate to how those taxes would be distributed. (it may still be better if enough revenue is going to housing dev).

So a ~10% tax rate for SECOND+ homes is still too small considering how many houses we need to build. I argue for 100% tax: pay that price every year if you want a SECOND+, that would completely offset a new house in compensation for tying one up).

If you are rich enough to afford a vacation home: you pay vacation prices. You don't get to use it as an "investment vehicle" we need to dissuade that mentality completely.