As an alternative to total tear-out and reconstruction, you might want to do a search for "mud-jacking" or "slab-jacking". Not sure where in MN you are located, but anywhere near Mpls should be a number of companies doing that service. Not a cheap proposition, but certainly less money and less invasive/messy than full blown reconstruction. The construction & engineering companies I have worked for in years past have used mud-jacking on a number of projects with good/satisfactory results. My Dad had his driveway brought back to "normal" with mud-jacking. Even saw a BIG slipformed grain storage facility brought to "plumb" with mud-jacking . . . and it looked like the leaning tower of Pisa.
