Barter or trading is the easiest way to make money as a world traveler.
Many travelers exchange a service for something of value, this saves the person giving real money. If for example a Hotel has many extra rooms they will often trade, but if the Hotel was full the would not. This works best when the person has too much of something, and it truly cost them nothing to trade it.
In Quito, Ecuador a man printed all the door numbers for the hotel in exchange for free lodging.
In Iquitos, Peru an American fixed the electrical problem of a hotel in exchange for free lodging.
Many people exchange a massage for other services.
Barter and Trade Defined: Barter is a method of exchange by which goods or services are directly exchanged for other goods or services without using a medium of exchange, such as money.