15 year old house with a walk out that is built in the ground instead of the house being raised up. so it has a concrete wall that is 24 by 45, 8 foot deep and it is leaning vary bad so they want it riped out and redone, I have suggested putting in a reataing wall and terraceing it out 4 leavels. MY ??? is has anybody done a tear out of this size, and what to charege for the tear out . I have some resource , And Iam getting bids to have it removed would you sub it or have the home owner take care of it. Any advice would help thanks.