Show price

Hi Guyes
I have a problem in my project i'm building a small E-store containt from: 
- 11 dropdownlists( each one for spesified category).
- 11 Buttons.(A spesifed job for each button is move lable value to another " kind of confirm show for user".
- 11 labels, and a Button has a "price" name.
Big error in my projct: to show price, must on user select all dropdownlists to be able show price in spicefied lable.

Now if user select only two or five catecories from  E-stroe, I can't give price for user, beacouse must on his select all dropdownlists.
How I can resolve this problm.

Thanks
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