I think it's more fair to compare prices by item of the same quality than the total amount of the quotation, which is to understand how the cost is being charged to you. There's no such things as free unless you've already paid for it (or cost in liao). Afterall, worth trying contractors than interior firms.
In some interior firms, what I understand sometimes the so-called interior designers are actually interior sales designers only. They can talk but no nuts about technical or pratical issues (you'll realise it when you probe further). Some are just interior graduates with not much of experience. They will think of some reasons to justify their worths / values.
At times, while you thought you are getting competitive pricings locally, you are just getting import furnitures - their factory and workers is from JB.
Hope this enlightens.