Duty is not payable on goods less than US$200. The value is based on the invoice/declared value of the package.
I regularly make online purchases (cosmetics, perfume, clothes, etc each less than US$200 at a time) and have never had to pay duties or taxes. The items I am buying are sometimes 50% cheaper than what they can be purchased for in this country.
I would be careful bringing electrical goods into the country. These types of items may be subject to import taxes and duties.