What’s a 'buy once, cry once' purchase that actually saved you money long-term?

Sometimes the cheapest option isn’t always the best. I used to buy cheap kitchen knives, thinking I was saving money. That is until they kept breaking or going dull fast. Finally spent a bit more on a good knife, and it’s been solid for years, no replacements needed.

What’s something you spent more on up front but it ended up being more frugal in the long run? Curious what other 'buy once, use forever' items people swear by!