Since a week we are collecting materials from a house that is in major remodeling. It's amazing to see than more than 90% of the things in a deconstruction has a possibility of being upcycled.
We really plan on trying to upcycle more material from sites we know of.
Just in isolation material, we saved around 300$. We probably saved another 200$ as we took the floating floors too. We would probably put that in several little houses we will build.
We also got wood, studs, tiles ...
It takes a lot of muscles and a lot of time but it worths it.