I'm wondering why the value of the individual coins in a mint set can be worth hundreds of dollars, when the whole set may only value out at around ten dollars.
It all has to do with the grade of the coin. Mint sets don't always have high grade coins inside. What year/type are you looking at, and maybe we can give more detail on why the value of the coins are $$?? Speedy
Krause can be slow to reflect current market conditions and then neglect to change the mint set price when they do update the individual coins. If you're talking about US coins it's as Speedy says; Not all coins coins in mint sets are high grades.