New home cost impact of rocks, trees, stream, grade in land

[Scott L.]

I have the possibility of investing in the development of two new homes (1 acre each) in my town. The neighborhood is exceptional and land purchase price will be lower than market, given personal contacts.

The land right now is about half filled with small-to-medium-girth trees. The ground is bumpy underfoot and our town is known to have rocks under the topsoil. There's a small brook on one edge of both properties. One neighbor have dealt with it by building a small tunnel under one side portion of their driveway. So net-net, lots of promise but also these topology concerns I haven't dealt with before.

Can anyone point me to guidance like cost increases to bulid, pitfalls to watch out for, and due diligence steps to take, to asset the impact of the grounds on building the house? I'm hoping for more guidance than "it's more expensive," "it depends", "talk to the zoning board", or "hire a surveyor", though I understand these are part of the answer. For example, how expensive does it get to remove stones, clear a field of trees, or flatten the property? Can a basement truly be waterproofed from a brook that's 50 feet away and down-grade? I'd be happy to read anything written about a developer's experience with 'bumpy' land. Thanks in advance!