Personally I am trying to be more self-sufficient. Growing food, cooking common items from scratch (like bread), learning how to repair things, etc. And so I put money into items that are both durable and help further this goal of self-sufficiency.

A safety razor and a 1,000 pack of blades is a recent purchase. Properly maintained, it will last forever, which will come in handy when Schick razors are $25 each.

I’m not sure how that scales up to $50k or $100k but it’s a starting point.

This subreddit is a good place to get ideas: https://www.reddit.com/r/BuyItForLife/