Should I buy SUV or Sedan if I want to become a Uber driver?

In the Uber’s driver app, you can choose to function as UberX (sedan), UberSUV (suv), or both. So you will have a choice.  If you buy an SUV, you essentially have a larger target audience, because you have access to those specifically requesting SUVs.    UberSUV will also pay you more for each trip, and this is enough to cover for the additional costs of MPGs and vehicle price.

With that said, if you are accepting UberX, you will be paid the lower rate, and you will still need to incur the higher gas fees.  Therefore, if you keep getting UberX requests, you will not fare as well as other sedan driving UberX drivers.  So at the end of the day, it's about how much in demand UberXL is in your market.