To find the total area of the octagon you can find the area of the rectangle that is created by the entire figure and subtract the areas of the four congruent right triangles.
(10 cm x 6 cm) - [4(1/2 x 2 x 2)]
60 cm² -8 cm² = 52 cm²
The total area of the octagon is 52 cm².
I say around 210-220 is a good answer
