Nedarim 47: Prohibiting Something That Doesn't Yet Exist

When the vow is on a specific property, how long would one be prohibited from benefit? For example, what if the property changes hands? For that matter, can one prohibit something even after it's gone from his own possession?! Also, a discussion of the off-limits property, with a question raised by Rami bar Hama. Namely, how effective is a vow when the relevant property changes hands? With several attempts to address the dilemma.