I discovered it's possible to enjoy many attractions for practically free or very cheap. I'll give you a few suggestions below: National Parks The national parks have camping facilities designated for those who like to travel with no frills or amenities. This means you can enjoy the fresh air and beautiful surroundings at a very cheap price. What's more, is you'll be surrounded by nature and animals so it's an unforgettable experience! The campgrounds usually cost around $30/day per person and they include: -Access to bathrooms (of course) -Water available (for drinking and washing)
Mexico / Tulum travel advice
I have been to the Yucatan. I recommend pleasant and safe Merida, rather than crime-prone Cancun or other places on that side. From Merida you can easily visit the fascinating Maya sites Kabah, Uxmal, Chichen Itza, and others. In Mexico City, don't miss a tour of Teotihuacan and be sure to spend at least a couple of days in the National Museum of Anthropology.
P.S.-- In Mexico City, do NOT take the pink taxis, which are not safe. Use only the equivalent of Uber/Grab.