Tax basis - Joint Ownership or Inheritance?

[Derek Tuohy]

Tax question.  I am joint owner with my mom on the deed of a rental property.  This property has more than doubled in value over the past 6 years through appreciation.  Regarding tax basis, is it more beneficial to gain full ownership upon her death from being a joint owner, or gain it through inheritance if she was the sole owner on the deed?  Its my understanding that if I were to inherit the property there would be a step up tax basis.   But if I were joint owner (as it stands now) and I decided to sell, I would owe taxes on all the capital gains from the time we bought the property.  FYI, she currently is responsible for paying the taxes and gains the tax benefits from ownership.  Thank you!