When I first started traveling for long durations, I quickly realized that my biggest expense was keeping my life in the USA alive. Once I ditched the apartment/car payment, I found that I could live substantially cheaper on the road than I could back home.
As an example, living and climbing on the beach in Thailand, I could pay for my monthly rent/food/beer expenses with a single day of billable work. I had a laptop along for exactly that purpose, and as a result I ended up padding out the savings quite a bit by living in a tin shack on the beach.
You think travel is expensive because vacations are expensive and that's your only experience with travelling. A week in Hawaii costs about $10k for your family all in, so naturally it must cost me ~$500k a year on the road, right? I'll leave it to you to do the math on what you actually end up spending when you're paying local rates for accommodation and travel in 3rd world countries, but the answer you're working toward is $500-$1000/month.