The laser cutting files are gouped in folders depending on the material needed. The dimensions for each sheet is part of the file name, for example: Sheet12_balsa3mm_500x200mm.dwg
Obviously for a 500x200mm balsa sheet you need to cut a 1m sheet in half and join the 2 pieces together with CA before laser cutting.
All you need to do is to explore each material folder and figure out the number of 1m long sheets needed.
The flat areas of the fuselage (vertical side walls) are made of 3mm balsa, and these are included in the laser cutting drawings.

The curved areas of the fuselage (turtle deck, belly pan, fin, etc.) are covered with 2mm balsa and these are not included in the laser cutting drawings since you need to manually cut and adjust them for a perfect fit. You need around 17 sheets of 2mm balsa (1m long) to cover the whole fuselage. Another 16 sheets of 2mm balsa are needed for the wings and 6 for the stabs, so in total 39 sheets.