Honestly, I'm shocked that the lease has a provision that the lease can be terminated if the property changes hands.That's a violation of the principle that "the lease runs with the land."

We had 2 escalation offers on our most recent sale and it definitely helped the “winner” and our broker was very ethical about it - I don’t think a buyer who offers an escalation would honor it without seeing another offer in writing.

I did a quick research and it seems many people are doing it and there isn't anything wrong ethically or legally, so is there something wrong in subletting for profits that I'm missing?

Whatever extra you pay on your loan goes toward principle for that month.  

@Patrick O'ReillyNOI is income-expenses, but the expenses for NOI do not include Principle and Interest.

There is a principle of 217K on the loan. 

Weither or not this is ethical is a different topic but it happens and I feel like that's highly beneficial for the buyer.Am I missing something?

What is my legal/ethical obligation to first people that signed lease but no deposit yet. 

I know my reply to this is quite late but the principles of finding and evaluating mid-sized apartments are going to be the same as for small or larger apartments but your management with mid-sized buildings is what will be different.

I agree with the principles in the post, but I think the content is fairly generic and "fluff"y.