Figuring out the profit on a product?

I am really struggloing when trying to figure out how much I am making on a product.

I have a product with several child products. Using business reports I can see what sales I have made over a time period, but annoyingly it lists each child product seperately, but I can easily add them up. However it doesn't show me the Amazon selling fees that have been charged, so I need to get that from somewhere, but where? I also need to deduct the PPC costs and I think I can easily get those figures.

Is there a simple way to do all this?