We just bought a house built in 1979. The walls are split faced block and slab on grade foundation. It is a 1-story house.

We'd like to keep the current slab footprint, but entirely change the interior layout. We also hate the split faced block and would want it stuccoed. We would also change a lot of the window and door locations. There is only about 30% of the walls that wouldn't have to be touched.

One contractor says we should tear it down completely, including breaking up the slab. He says it would be more cost effective than cutting the slab to replumb, cutting to add footings to add the 2nd story, adding stucco to split faced block that would require a lot of material, moving windows/doors would require knocking a lot of sections down, etc. He also said there is more chance of water intrusion and termites when cutting the slab for new footings and plumbing.

Another contractor says take it down to the slab, then rebuild. He says moving plumbing is no problem.

Yet another contractor says we could probably keep most of it.

I realize cost for materials and labor differ around the country, but which contractor should we believe and which option would be the most cost effective? labor and materials is very costly where we live, so I don't know which option will be the most cost effective and still be considered a quality job (of course new build should be the best quality). I don't know the quality of the slab (e.g., level, cracked, etc.) other than there appears to be some spalling along the edges of certain parts of the house.

Anybody been in this situation? How should we proceed and figure out the right path? Our architect also says tear down, but we are having a hard time knowing that we paid for the improvements when we bought the house. However, we want the house a certain way, so we are willing to spend the money unless we can avoid it.