Group together with other owners together can do better.

If it's still under warranty, you can asks your own contractor to do it first and claim it back later (more than x days of notice without response, the x I think it's 14 days if I remember correctly, correct me if I'm wrong) .. but you know la this kind of thing, "how smooth and how fast" you're able to get your $$ back .. perhaps you've to bring it to court after all. Next time when you buy new project, consider thoroughly the devr background, even worst if project go abandon.

Better still, group together with other owners that facing the same problem.

TS .. answered here .. http://forum.lowyat.net/topic/2525856/+20