-There should be a finite window for the departure, assuming there is a full lease to be fulfilled/not fulfilled.

Like a self-fulfilling prophesy  The fact that it gave you a hinky feeling goes to show that it's not something you'd be comfortable with, so that's a good indicator that your tenants wouldn't love it either.You just can't treat people badly, and then expect them to be a long-term ATM machine that spits out rent every month forever.But, of course, your PM probably makes money every time the place turns over, so they don't care if they are irritating the tenants and having to get a new tenant every year, because none of the tenants want to stay after their lease is up.

It's just saying that both sides have the same rights - if one side doesn't fulfill their end, the other side can terminate their offer or sue for actual damages. 

If one side cannot fulfill its terms (pay rent) the other side can do whatever the contract allows to enforce it (eviction?).

I emailed the sellers attorney with the following-"It has recently come to my attention that the terms of the contract that the seller signed, have not been fulfilled.

A lot of property management companies/landlords have it written in for the opportunity to find a qualified tenant to fulfill the remainder of your lease.

This fulfills that basic principle of landlording.

Best of luck in your journey - it's going to be a wild but very fulfilling ride! 

Verifiable rental history for a period of at least 12 months, in which all the lease terms have been satisfactorily fulfilled, is preferred.

Make for a terribly co-dependent population and only furthers peoples problems, and hence our societal problems.