There's no photos of the bottom... The deck looks good. I would assume the bottom would also be fine.... Condition looks like 7/10, maybe...
Just put you eye over the bottom, and make sure it's not twisted, or warped... There's a chance the bottom either has some de-lamination - from the sun, or even worse, some shrinkage of the foam... but you will notice that... If the bottom side hasn't been "baked" in the sun, then that board is a (potential) bargain!