do i have to pay in american money or peso moneys

As your travel agent....depends on your hotel sometimes

Well, when booking with.by your travel agent you must pay in the local currency. If traveling with a "flight only" to the Dominican Republic, you can pay in Dollars or in Dominican Pesos. But! you must take in mind that it is always cheaper to book by a travel agent! So don't worry about the currency to book. By traveling to the Dom.Rep. you need some cash money (us Dollars) to pay at arrival airport (10 us) and by leaving (departure) 20 us per person (if not included in the package) For the rest of your stay you can take daily some money out of the cashier nearby your hotel ( Dominican Pesos no Dollars!).
I hope this helped a bit.
El Pinguino