A close friend of mine was a collector of various things. He had a huge (and financially-meaningful) collection of comic books, as well as a great coin collection, and a beautifully-conditioned 1964-and-a-half mustang.I'm sure we must have some hobbyists on here such collectors of coins and other valuables. Have you considered collectibles as an investments?
He never collected any of these things as investments -- he collected them because he enjoyed doing it. He bought (and kept) Superman #30 because he remembered seeing it in the store when he was a kid. He bought (and kept) Spiderman #11 because he liked that comic when he was young. He let me read -- and keep -- a few of his older Justice League comics, which are fascinating to me not because of the financial value but because I find enjoyment in them and they remind me of him.
Over time, as he divested himself of most of these collections, he looked back and said to me: "You know, I'm very lucky for having made money off of these things, but more than anything, I simply enjoyed having them." He made quite a lot of money off of these collections, but it was a very long time before he realized any financial return on them.
So, I guess that's the advice that I'd leave you with. Investing in these types of things are hard and (in my opinion) unlikely to yield reasonable returns in your lifetime. You're far better off collecting things only if you enjoy doing so.