Probably most books read and kept in a private home. Maybe most knives not in a collection in a commercial place. Largest personal tool collection not in a business. I seem to collect hobbies like a dog gathers fleas and each hobby, skill, or talent requires a different set of tools....and usually another portable building. I really would like to have a fourth outbuilding but my wife says NO!!! I'm going to close in one of the big carports I think. It already has the sides so all I need to do is close in the ends and seal it.
Over the years I have done a lot of things for a living and if I have any special talent it is in my ability to see something done and then teach myself how to do it in a very short time. I learned several skills totally from books that I then added to my business. That made it pay to have the tools and that knowledge.