I’m interested to know what their response is to the fact that it’s impossible for the rates to have risen that much if the scenario of the loan didn’t change.

What that difference would be, if any, is very hard to say.So, yes, the would-be-buyers made a mistake and it's their responsibility to make you whole.

I used to do triple this amount of rehabs for my REO clients with only a 4-5 person team and the same field contractors.The answer is making the field contractors 100% responsible for everything instead of hiring dozens in your office.  

As an investor a 10% return wouldn't compensate me for that kind of risk as I'd be inheriting the problem if it was a bad deal OR only getting a 10% return if its a good deal (i.e. no upside)Not criticizing you - just curious on your response to that issue. 

My response now is always "what do you want real estate to do for you?".

Hi Ben, sorry for the delay in my response.

Last question.. since i do have a property mgr..was it their responsibility to tell me about water bill not being paid? 

I understand what @Blair Poelman is saying that you give up some of the fiduciary responsibility that the agent owes you, however, in a competitive buyer's market, it can be helpful to get more of a competitive advantage and if it comes between you and someone else offering on the same property and you are using the seller's agent, in my experience, you usually get the deal.  

The answer is simple: as much as you can spend responsibly. 

Very responsive, thorough and active.