Do you pay taxes? It is a gamble, there is no firm answer. Because of the season, Dominicans returning to the country with gifts are usually waved through Customs without much fanfare. Foreigners may be checked, but even that is iffy.
I checked the EPS website for the tax on a US$ 120 microwave and it indicated US$ 40 tax. It is best to be prepared to pay. However, if you don't fit any harmful profile when entering the country you also will most likely be waved through Customs. Regards, PJT