In my career of doing at least a little of everything, I did run a family portrait studio for about 6 months right out of college. One thing I can tell you, and which has been confirmed by some other experiences over the years, is that sometimes the low-income folks will spend more money than you would think on something like this. First off, they're getting a nice sitting for free. Second, they want to have pictures of their family. Family can be very important to them and they may not have much else in the way of a family gift, so do your best and ty to make the print prices as reasonable as you can.
Regards,
Andy Pearlman
Andy Pearlman Studio