I know a couple of people who tried to do this and never found the right formula to make it cost effective. The clients want a lot and pay very little.
My suggestion to make it worth your while is to be the guy who shows up at family reunions and tapes people talking to each other. Good audio is the key, because it will be a noisy situation – camera mics won't work. But the oft-told stories will be great and everyone will feel comfortable doing it. Plus, you get everything in a day.
Memorial videos are another idea if you can work fast. Still photos to music. I was hired once to set up in a room away from the memorial service and folks came in and talked about their memories.
The common denominator is to be where families naturally gather.