How big was the first 4 bedroom house for habitat for humanity of pike county pa?

I didn't find specifics for your location. However habitat homes are typically small and have few architectural features so they can easily be built by volunteers. Most are ranch homes on a crawl. In our area, a 3 bedroom is roughly 1000 sq ft on a crawl space. A 4 bedroom would be about 1200 sq ft on a crawl space.