Vipers, slaves and rent controls.

In this excellent article there are many examples of how policies - although intended to do the right thing - have unintended consequences.

An extract : "in the Italian town of Abruzzi, which had a problem with too many vipers. To motivate citizens to kill vipers, the town fathers created a viper bounty to be paid for dead vipers. "Alas, the supply of vipers increased. Townspeople had started breeding them in their basements" (p. 58). The problem, of course, is that the town fathers rewarded the wrong thing. What they wanted was not more dead vipers, but fewer vipers in the first place."

The same is true of rent controls. By using a supply and demand diagram, it can easily be seen why rent controls have led to a shortage of rented accomodation in cities such as New York. More interesting is how landlords are now trting to reduce their costs by cutting back on maintenance, free utilities, maintenance and free parking.

Also new fees such as 'key fees' and large fees paid to estate agents for finding the apartments.