You know many states south of Missouri cannot have basements because of their soils. Basements are usually found in areas with some bedrock of sorts.
I know for example in Texas, Louisana, and the likes could not support a basement and it would actually sink and fall away.
Clay soils and a mixture of clay and dirt will not support a basement let along a concrete slab foundation.
Check this out with authorities and see if your soils will handle it.
Then, personally to build a basement in an existing home is a waste of money and more than likely a deterent to market value and one expenditure that you may never re coup. You have many structural issues to overcome and to make sure your home is still sound. Add on to your home if you can horizontally.