I answered that my go-to weakness for the basic interview question is that I'm too nice, and it's absolutely true. But the positive that comes out of it is that that trait would cause me to be extremely honest and upfront with customers so they can see that I'm only trying to help them with their financial situations and not a sleazy dealer that is only trying to make a buck. She really liked the answer and went on a 2-3 minute lecture about being more about customer service than making more money.