Buying an investment property with negative cash flow puts a lot of financial pressure on you.  

Quarterly earnings pressure.

Also these loans are fixed rate for 30 years so cash flow can be projected without the pressure of a Hard Money lender and high rates/fees they all usually have.

Because then its not a questi9n of "if" you'll spend the money to replace them, the question is "when" and in what situation it is going to be.I prefer to take care of these things in advance, BEFORE I'm occupying the property with a tenant, because no one likes the aggrevation and the pressure of taking an emergency repairs and it'll always cost you MORE than if you were doing it from the first place.

I think the big thing in your spot is to have your targets and goals, constrain them with time so that you have some pressure to hit them, but also be okay with things proceeding at a measured pace.  

Good deals aren't always available or even chosen when available simply because of the time pressure.

Should make sense that the areas that saw the fastest growth ie Bosie, PHX, Austin will see the most volatility and the most downward pressure. 

." - link"Common worries are that population aging and decline result in labour and skills shortages, weaken economic productivity and innovation, slow economic growth and development, impose unsustainable fiscal pressure on governments and people, lead to cultural and ethnic shifts in societies, and weaken the political and military power of countries.""

This isn't a bad idea because it takes less pressure off of your AC units.

Your realtor should be able to gauge your leverage and advise you on how to negotiate from here.