Program to selectively merge Excel files

I have 4 Excel files which I need a program to read, compare one of the columns (telephone area codes) on each file, select the lowest price which is on another column and write the selected "best" row to two new Excel files each one with a different column layout The problem is that on a file we can have a telephone area code as 0057234 and on the other an area code like 00572 which would obviously comprise any area codes below that one (0057234, 005722, 0057241...).