The picture above shows Cristian shoveling concrete into the hole dug for the new foundation (doesn't their house have a great view?).
The new house is being built around and over the old one. They will build up the walls, they fill in with dirt between the old house and the new walls to the level of the old floor. Once they have the roof on the new walls (and over the top of the old house), they'll take down the old house and pour a floor around the old floor reaching out to the new walls. This way they have a place to live while the new house is being constructed and they can make use of the old floor. Plus, their land is really sloped, and this way they don't have to level a new place to build a new house.
The supplies came from a politician. Elections are coming up soon, so politicians are in a rush to help the people- giving away building supplies, working on road repairs, etc.
There are five girls from Trinity Western University living up in Los Higos right now, and they helped off and on throughout the day with the construction. You can't see it well, but here they are filling a large can with rocks to be thrown into the concrete for the foundation.