subsummary problem

Hello all! I have an inventory problem that probably has to do with subsummaries.

I keep track of every part that leaves our office by serial number. Every part falls under a specific category. Each part also has a price but these prices vary between the parts themselves. What I want is to show that within a specific category, there is a count of how many parts are at price X with a total sum, while the rest of the parts are at price Y with their total sum. I want to avoid giving a specific value for these prices because they vary so often.

I have, so far, a subsummary with the break field "category" that lists the individual serial numbers and the cost of the part (all underneath the specific category), and a trailing subsummary, with the break field "cost of part," that contains the "total number of parts" and "total price." The problem is that the "total number of parts" and "total price" are under each individual serial number instead of after the last serial number with price X.

Is there any way to have FM split the parts into groups by price?