To assist lower-income families to acquire home ownership, the Housing Authority (HA) introduced the Home Ownership Scheme (HOS), the Tenants Purchase Scheme (TPS) and the Home Assistance Loan Scheme (HALS) over the past few decades. However, the HA had accepted the Government's recommendation on cessation of the production and sale of HOS flats indefinitely from 2003 onwards. The small number of unsold and returned HOS flats would not be offered for sale as subsidised housing units before the end of 2006. While no new sale phase of TPS flats will be offered after the launch of Phase 6B, the HALS was terminated with effect from 14 July 2004.

The HA decided in January 2006 to offer for sale in phases the unsold and returned HOS flats (collectively known as surplus HOS flats) from 2007 onwards to Green Form and White Form applicants and endorsed the proposed sales arrangements for the surplus HOS flats.