I am working on something for the web to make it easy to find the foundations. Give it some time and you'll see it. But it sounds like you found the foundations anyway.
As for how many more houses?... Actually, if you do a lot of walking you can find various locations not publicized yet. I'm sure many have found the area near the roped off entrance that has A LOT of broken glass and other junk in a "hole." Based on what I can find this area has a lot of stuff from the 1930s, 40s and 50s. I do find some items from the very late 1800s but not very often. At the moment I suspect that this was the remains of an old house but it was used as a garbage pit for a long time. By finding material from the 1800s it may very well be older than the foundations west of the cemetery. It will personally take me a long time to narrow a date down. Old maps didn't indicate anything there even though the two usual house foundations are on the map. Using aerial photos from the late 1930s indicated that something was in use as far as a very small road going to the location (off of the now closed Midlothian Turnpike) but as far as any structure it looked long gone. The little road was probably just an access road to dump their garbage.
At the moment I am not disclosing some of the other locations but once I can find out more information and I am done with removing old artifacts to date and catalog then I will go public.
Pete