Depends on your requirements I guess. I think a lot of the pricings are high because most the interior designers redo things or jack up the prices on your carpentry and wet works. I had one designer quoting me 30k for my master bedroom. I DIY and its 2460 for contractors and 1.5k for the interior designers. U do the math.
i feel that certain things you can save on, you can try to. eg. inbuilt cupboards or storage areas are more expensive compared to just table top installation. for storage can get those from ikea as its cheaper there
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