We have fully paid a HDB flat and we are currently below 55 years old. I have bought a private Condo and will be TOP by June 2015. If I do not want to set aside minimum sum (MS), do I need to sell my flat by Dec 2015? After I sell my flat, can I still use all the flat money (including CPF & Cash) to pay my private condo? And if I am able to use all my CPF & Cash to fully pay my private Condo, and would like to buy second private Condo, do I need to set aside MS? Will it be half of MS or full MS?