One thing I've done in past marketing-related searches is to watch for a mortgage that has extra pages. The systems around here tell you on the initial search page how many pages were in the mortgage. 15-16 will be a "normal" mortgage, 19-20 will have a rider of some sort. You'll have to weed through those to discard the 1-4 family ones, the balloons (although you might want those, too), and the other rider mortgages, but that's been the best way I've seen.