Unconventional items as an investment is not exactly sustainable. You might make mutiple times of profit on one hand, or the other hand, nobody might be interested in certain items at all. There are also the time factor. Some items appreciate in value, while others depreciate. Hindside is always 20/20. You will never know until it happens. Unless you understand how the market works and really have passion in the items you are looking for - this could be an investment, but definitely not something that can generate recurring income in the long run... unless... you really know the market and the dealers that well... Otherwise, as a layman, it is either 1) to simply buy and collect if your are indeed into it for the passion 2) always nice and fun to see how people scalp and how people are willing to pay high price to buy.