From what I understand, a hot water dispenser is used in a sink, usually in the kitchen, to provide near boiling water for making tea, pasta, and such. It’s not for showers or washing dishes or anything like that.
So-called suicide showers provide hot water by heating water coming out of the shower head. These work okay but the water isn’t always that hot. A These are used usually in a home that doesn’t have a hot water heater that serves the house. In these types of homes, which is how many Costa Ricans live, there is no hot water in the faucets or washing machine. Some homes use a propane gas system to heat the water in the house.
Most if not all North American-style expat homes to buy or rent have hot water heaters and hot water works just like the U.S. or Canada.