According to this article, citing interviews with people Brenda Heist knew in Florida, she was NOT homeless during the time she was missing, at least not all of the time. She apparently took housekeeping jobs and often lived with her employers. She saved enough money to get a car, and she also had a cell phone and a Facebook page for a time (they were both disconnected eventually), and even dated once in awhile. She said she had no children and her husband had died.
I had actually been skeptical of the whole “homeless for ten straight years” thing myself. Very few people can survive on the street that long, especially women. The reasons I think are pretty obvious. It appears Brenda was on the streets sometimes, perhaps even for months at a time, but certainly not all the time.
Needless to say, the people in Florida who helped her out and thought they knew her feel shocked and betrayed. Though, I’m sure, not as much as her actual family.