If there isn't one, single cardinal rule in personal finance, this one certainly comes in near the top of the list: If you want to save money on something, do it yourself.

But sometimes, it's well worth the money to delegate. Paying someone to assemble IKEA furniture is a good idea if the assembly process always leads to a fight between you and your significant other. And if something went wrong with your plumbing, it would be cheaper to get under your sink with a wrench — but would you even know where to begin?