[Plugin: price-calc] some coding questions

First of all, thank you for this great plugin! it is really helpfull to give my clients a better view on my prices.
But it could be better…
I am a wedding photographer and configuring your plugin so that my clients can choose an album or a print and get the price. Now I want an option that they can say how many albums and how many prints they want, so that the previous price they chose is being multiplied with it…
Is this possible? And how do I do it?

http://wordpress.org/extend/plugins/price-calc/