If you are looking to change money on the main drag between the Hyatt and Hardy's supermarket, take care. Three I tried all did their level best to rip me off - I walked out of all three. It is not as though their rates were "too good to be true". I had just almost run out of Rupiah and the wife wanted to buy something in one of the small shops.
I mentioned this to the tour operator and he said they were n notorious for it.
The booth at Hardy's or the circle K shop almost opposite have almost as good rates without the hassle.