Is My Property Managment Bullying Me?

[Bob Beach]

We've had investment properties, out of state, for the past 5 years.  We've moved a few houses (out of 6) to different PMs due to not being happy with honesty, fees, etc...  Now, we have a new company and they have been doing rehabs and repairs at a decent price. But now, we just finished a house, got it rented but the house didn't have central a/c.  We'd talked about installing window units, till more funds came in then Central air.  The house originally had a window unit installed in the wall.  They did say, the house already had heat.  So, we decided to bite the bullet, do it right and get central air.  Got the estimate for "central a/c". This is how it was worded in the estimate (attached).  In the past, they gave me an estimate for just an outside unit at $1300 to $1500, on another house.  Now it's installed and a few weeks later, the PM texts me and says, (attached). "Bad news, the inside unit can't keep up with the larger outside unit". And, "since I only approved the outside a/c unit, we now need to ad the inside part at another $1300." I argued, I didn't know there was an inside unit since it had a window unit in the past and I thought I was getting a complete Central air.  And, who installed an outside unit that was not compatible?  They now say, "The inside unit is failing". I ask, Failing or can't keep up.  They respond, "They mean the same thing". 

  We had another disagreement where the monthly statement shows, "May and June" but they insist, it only means "June", but I wont get into that. 

I feel like, they screwed up on the A/C and they act like I don't understand their "terminology". Is there something about real-estate terminology, I don't understand or am I being bullied?  Maybe a third option? (I'm just a complainer)  Thanks for thoughts...