I tip grocery boys a minimum of RD$35, maybe 50 if we park a long way away or if it's a heavy load. They seem fine with that.
Since 10% is already added at restuarants, I'll tip an additional 5 and maybe 10% if the service is good.
We'll give RD$10-20 to street people IF they seem unable to do any real work. Sorry, the guy who lost a leg does not count, nor the Haitian with the rental baby. Elderly and infirm get it.
We will occasionally give maybe RD$50-100 to people looking for donations for operations if they seem legit, and to kids raising $$$ for a special school activity.
If we have time, we'll get the car washed at some charity event, maybe RD$200.
I'll tip the water guys RD$50 because they will lug eight-ten 5g jugs into the house, two at a time, and maybe two upstairs.
I'll tip the gas station attendant RD$50 if he cleans the front and back windows, and checks the fluids, and maybe "keep the change."
I pay my handyman RD$500 just to come to the house, and $200hr. for any work he does. He comes on a moment's notice when needed. We both win.
I'll maybe pay a "watchee" of the car RD$50, more if it's a legitimate vendor say at Carnival.
I'll tip a delivery guy from restaurants or pharmacies RD$50.
WE always make sure we have RD$25 coins and RD$50 bills available.