Hondata? Woahhh, niceeeee and wise choice bro...
Do it once, do it right.
As for exhaust, i dont think it will cost you a bomb. It mostly depends on your selection for muffler/back box. For ori Japanese brand new turbo muffler, expect to pay more than RM1k...
If you are on budget, chop shop/mudah/lelong/zth marketplace will be your best friends. You can find used ori japanese turbo muffler for less than half of the price of brand new. As for the piping, the price different between exhaust shop is relatively small. Go for 2.5" stainless steel straight piping.