We did the demo and removed the carpet and padding to try and reveal the cement slab floor. 

The labor quote is in the ballpark (assuming they will properly dispose of the carpet/padding/debris).  

And the bottom line is America is the land of small business and running a stable of rentals no matter if your lucky and you don't have to put much time into it or your working it full time .. its a small business.. these are not investments that you just click a mouse and all goes well.

The more trustworthy and competent you are to a seller the less need they have to contact more people.Go watch the movie "mouse hunt".

Did you have felt pads under the feet of your table and chairs?

Ours has a waiting list and the pad rental is better than a MHP. 

Find one with an underlayer attached, and if noise is an issue put a sound suppression pad underneath.

If the pad is just sunk, then mudjacking will be the way to go.

I would say right now is the time to negotiate a great deal as your numbers need to be padded right now and have potential to pull out most of what you put in.

That had the padding attached!