You can pretty much easily assume that touristy areas tend to be very expensive for obvious reasons.
Going to less touristy areas not only save you money, but it also saves you time because it’s less crowded.
It is also one of the cheapest ways to travel.
An example of this is when traveling to Portugal, the best place to get the highly sought-after dessert, pasteis de nata, is to go and line up at Pasteis de Belem.
Don’t get me wrong, Pasteis de Belem has the best pasteis de nata, but other pastry shops nearby sell the exact same thing and you can find pasteis de nata all over Portugal.
This example is more for food, but finding accommodations in less touristy areas will also save you money.