A slew of Chinese second-tier cities announced new restrictions on home purchases Wednesday, as the government continues efforts to prevent a housing market bubble. China Securities Daily reports the new measures include restrictions on how many homes a family may purchase as well as higher down payment requirements. In particularly hot markets such as Sanya city on the resort island of Hainan, down payments must now be at least 50% of the purchase price. The moves come as restrictions in first-tier cities such as Shanghai and Shenzhen have proven effective, with February new home sales down almost 50% year on year.