2006 Nissan Sentra, Carmax- 11500 (30k mi) (ripoff?)

[csaunders15]

I just bought a 2006 Nissan Sentra SE from carmax and out the door it was 11500 and I thought it was a great deal until I got home and started doing some research. The car has only 30,000 miles on it since it is spotless and hasn't been drove much apparently.. I thought I was getting a heck of a deal until I went home and found out the MSRP on them were 13,200-18,300 brand new. I have five days to take it back and want to ask the community here what they thought because I am not the best with cars. I also looked on Consumer Reports and it says this particular year/model has a "worse" rating for the fuel system. From the looks of it the fuel pump is usually the thing that keeps on getting replaced on this.

Should I take it back?

Thanks for any advice.