To subtract the MIN of a group from the MAX of a group, and only use 0 numbers in the group, you can follow these steps:

1. Select the range of cells that contains the numbers you want to use.
2. Use the MAX function to find the maximum value in the range. For example, if your range is A1:A4, you can use the formula =MAX(A1:A4).
3. Use the MIN function to find the minimum value in the range, but only for values that are greater than 0. You can use the following formula: =MIN(IF(A1:A40,A1:A4)). This is an array formula, so you need to press Ctrl+Shift+Enter instead of just Enter to enter it.
4. Subtract the result of step 3 from the result of step 2. For example, if your MAX value is in cell B1 and your MIN value is in cell B2, you can use the formula =B1-B2 to get the result.

This should give you the result you are looking for, which is $450 in your example.