Are speculators the problem is it the fact that housing prices are always expected to go up due to such limited supply? Instead of targeting a symptom, like speculative investment, why not target the root problem of prices always going up so that people can afford housing?
But then what is your description of the root of the problem?
At least in cities or places with a trainstation here the demand versus supply is out of band. What do you want to do against growing population and limited space?
