The survey to a catamaran or in general to a multihull in many respects traces an inspection to any other type of vessel. However, on multihulls the structural areas change compared to monohulls. Also, the sail plans change if sailing catamarans.
In my profession as a boat surveyor in Italy, given the wide spectrum of construction types, I had to analyze the multihull from a theoretical and structural point of view.
Long time ago, catamarans were the prerogative of sailing between coral atolls with constructions made of wood and otherwise natural and soft materials that absorbed the stresses on wave passages. Now, we face the mass diffusion of extremely high-performance and rigid multihulls that, if excessively stressed, are not able to withstand repeated impacts on the waves due to the often disharmonious passage of the double hull.
Life aboard a catamaran is certainly full of comfort and stability, so what could possibly alter this peace of mind?
The neuralgic areas are the transoms, the junction of the transoms and the mast foot; therefore, a structural survey on a multihull will have a focus on these elements as a priority.