Once sign reno contract, cannot take items out?

[Terraces 0]

Along the renovation journey, there were some changes to our reno ideas and we had to change the reno item, e.g. from false ceiling to Lbox, which is much cheaper ($200 to$500) than the former. However, our ID from a Casetrust - accreditated company indicated that as we've signed the contract, we have to abide by the indicated items in it and there will be no revision (lowering) to the prices even if we settled for a cheaper alternative in the end. That means, we have to pay the final quoted amount of 40k even though we have amended/omitted some items and the revised actual costs may only hover around 39k to 39.2k. We have proposed to them to add in free minor works to make up for the shortfall in the "quoted extra costs" in the original signed contract but apparently this is disallowed.

Is this true in a standard renovation contract? Can anyone assist?

Edited December 12, 2017 by Terraces
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