Rookie question regarding spar

Still looking at buying this Ercoupe, and it has some wrinkles in the fuselage. The spar is allegedly in solid condition as verified during the last annual, seller's representative does not know what caused the wrinkles in the skin. My question is how can I tell if the spar is in good shape? What does that look like? Two pics of the fuselage wrinkles in case that brings up another issue.

Thanks in advance!

W