[Q] Is that anything that i can buy for a safe long term investment?

So i have a decent amount of money in my wallet which i was saving for a deck but it went out of stock. RAM prices aren't gonna fall this year so i was thinking about buying a risk free skin/items, kind of like you buy S&P500 when you don't know anything about stock market.

Are there any sorts of items that can give me like even around 5% assured return (excluding steam tax) or am i daydreaming?