It's not uncommon for people who are candidates for housing via HfH to volunteer their time...
more manpower = house get built quicker = higher chance the candidate gets a home
I did that once. My moms office was doing a teamwork excersize, so they had to help restore a house.
My mom is a cow so she brought me along to make up for her uselessness
A bunch of corner cutting office customer support people. We did such a horrible job on that roof, I bet the habitats people had to redo it all the next day