Calculate ideal wood beam number

Hi, I got model of my garden house complete. Now I try determine best "shoping list" .. House is made from beams 10x10cm  and 10x8cm ..  I can buy beam at sizes : 3mx10cmx10cm and 5mx10x10cm etc. How can I calculate in solidworks best shoping combination to minimalize waste and safe money ? It is possible ?

Thanks a lot guys.

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