I am in the design phase of building a new home and I was wondering about a very rough estimate for a excavation, basement walls, and basement slab for 2600 sq. ft. and a 4 car garage. The soil is easy to dig. Lot slopes from right to left about 6 to 8 feet in the length of the house for a walkout. Does anyone know about how much that would be? 20k? 30k? 40k? Any input would be much appreciated.