All three are great quality. All three (and many other “lesser” schools would prep you for grad school - and your career is dependent on what you want to do?
Where do you live? Where is home - i.e. which state? Where do you want to end up - in the US, internationally?
I assume you are a US citizen? Otherwise you will be going home anyway most likely.
In a “rank” it would be Duke, Vandy and then far below UNC for econ.
If you were my kid, you’d be going to Vandy (regardless of career desire) - no questions asked - because it’s a top top school and you got an unbelievable price.