Thermal imaging is obviously the definitive issue in any
boat purchase. If the thermal image shows anything that might be the slightest bit amiss, take a chainsaw to the boat and destroy it so that no one else has to deal with the trauma that will be associated with it.
If the thermal image seems ok, have the boat hauled and put it in a custom
cradle in a shed
on the hard for 10 years. This is to help it to equalize the pressures and ensure even drying of the smallest problem areas that don't always show up on thermal images. After this is done, take another thermal image to verify the stability of the situation. If there are any doubts, repeat this procedure as often as necessary. When all thermal image issues are totally resolved, you can launch. To ensure that nothing bad happens (thermal images can be difficult to interpret, as others have mentioned) tie the boat in a slip (NOT on a mooring) and DO NOT SAIL the boat for another three years. Then have another thermal image made. Compare it to the initial ones and act accordingly. This may involve hauling the boat again and putting it in the shed, but the definitive nature of thermal imaging calls for it. Following this process will enable you to set sail knowing that your boat is thermally secure.
On the other hand, if your surveyor looks over the boat and finds some delaminated areas, believe him (or her), have them fixed (or fix them yourself) and go sailing.