I asked this question in the Wisdom of the Crowd:

What is a fair compensation to an owner of a repossessed HDB flat

Here are the responses: (41 Votes)

44 % - Current market value
24 % - Current market value plus 20%
22 % - Current market value plus 30%
10 % - Current market value plus 10%

See the pie chart at:
http://www.tklcloud.com/Crowd2/chart.aspx?ID=2638

CLick here to vote on the current issues:
https://tklcloud.com/Crowd2/active_issue.aspx