My wife and I are considering buying a 16 year old farmhouse. It is built on a concrete slab which has settled and there is a "wave" about 8" across and 7 feet long in the tiled hallway between the kitchen and dining area. A building inspector said it was probably just from settling and not a recent occurrence. I want to get rid of the wave, get rid of the tile, and replace with hardwood. The tiles are not cracked nor is the grout. The "wave goes about 1.5" wertical. Is it expensive to repair this problem? How do we go about it? Any rough cost estimates?