If Earnie sues, the most likely result would be: Earnie wins, as the modification was due to unforeseen difficulties.
In the given example, firstly Earnie accepts for doing the exacvation work for Jamie for $3000. This is because of his assumption that the soil will be easily excavated since the soil in the other lots was normal and there were no excessive rocks present which acts as a hurdle for the excavation.
But, whe Earnie starts to do work, he finds diufficulties in exacvation work since the soil was rocky in her lot. Hence he $2,500, which Jamie agrees to pay first but later refused to pay that extra amount. If she refused to pay the extra amount at the initial stage then she will win but in this case she accepts tp pay for having the work done. Thus, if If Earnie sues, the most likely result would be: Earnie wins, as the modification was due to unforeseen difficulties.