I think, the exhibit contains inaccessible parts should disappear (before they are returned), showing a message about it, which can be disabled. And I do not think that this is something terrible. While finishing the post I got this idea. If there is no part of the ship, then it can be pack to box like statues in some museums, and put a sign that exhibit on renovation. I think we should put the original set of parts. If the texture is what changed from version to viersion of mod, nothing to worry about, applied as well as to the ships in flight. If the part has been removed, see above. IMHO What you come back on Kerbin, that would be exhibited. If you threw out rover, and too lazy or could not get it back, you have no right to exhibit it. I do not think that the space station can be exhibited in the museum. If you return only the landing capsule, you'll get tens or hundreds of times less income than returning the landing capsule with engines and research modules. Besides you are unlikely to enjoy browsing through a museum consisting solely of capsules for the crew. So I think most of the players it will fill what is unique. And yes, I thought from my post, it was clear that the player decides to get instantaneous price returning parts or to put such a beautiful and legendary monument to the history of space exploration.