Ignoring the fact that undeveloped land in PA is going for about $3mm an acre, What you’re talking about is commonly known as a subdivision. You need to account for roads, utilities, zoning, etc. im also fairly certain you would run into nimby problems even just by trying to subdivide and sell individual lots.

You would also have no way (that I know of) of only selling to people like teachers, firefighters, etc because of fair housing laws. There’s may be an exception for military.