Contemporary Motoryachts are built with very advanced technologies which are resistant to sea water and far more stronger than ordinary wood planking system.
The new generation materials are being chosen according to type of the vessel, either for speed cruising or sailing performance. Some boatyards build with western system epoxy laminated wood or GRP (glass fibre reinforced polyester), some need a displacement yacht for long range cruising and some ask for a lightweight, fast cruising vessels. advanced new generation  motoryachts are built with closed cell PVC plates and epoxy laminated grp system which is called compozite system which are more expensive.
One of the most important issue is electrical wiring system to be able to build yachts which performs better, thats why we recommend you to expertise a yacht before buying together with a captain and an electric technician.
İt is also crucial to know where the yacht has been used, the waters in which she has navigated in order to decide if she has been subject to constant severe weather conditions. You need to measure the engine compressions to verify the conditions of the main and auxiliary engines as well as pumps and airconditioning system.
İf the boat is made of fiber glass then you need an expert to see if she has been effected with osmosis which is as crucial as saying yes or no. if you are buying a steel yacht, then you need to measure the hull thickness and verify if she has cracks in weldings.
When considering a second hand classic wooden yacht, one has to know what kind of wooden is used for building and if there are any rotten parts under the paint which could be the worse deal you have ever made. Reconditioning of a wooden yacht is quite difficult and requires countless time and money since you cannot repaint her unless otherwise the hull is completely replanked, renailed and repaired. The furnitures are the tricky part where you might be impressed and decide to buy a yacht since  you need to be able to calculate the final figures…