The initial charge for the construction documents is $10K.

Being in the construction business for about 30 years and having a real estate broker license in Texas for about 30 years gives me a unique answer probably regarding your issue. 

Ended up switching to a new property management company that also has a construction arm of their company.  

My research leads me to believe that a specific mortar needs to be used, as the stone and antique brick are not as strong as modern day products/construction.  

Your agent should be a second pair of eyes and if you were present during the inspection it is likely the inspector would have told you verbally about any major issues while you were there. 

First step is I would go back to the inspector and ask him to expain it.

I have two lots I'm going to build new construction on.

Meyers ( lehigh Acres) on brand new or near new constructed homes ( minus Chinese drywall) for 25 to 40k each.. these homes 5 years before were selling for 250k.. in my mind in that time in space.. that was probably one of the cheapest places in the first world to live.. brand new our near new home for 30k  US health fire and police.. 

There is some interesting construction techniques that I haven't seen too often.

I analyze the property, and estimate rehab costs (with inspectors and contractors), add a buffer for unexpected repairs, as well as an ROI comparison of setting the property up as a rental vs. selling the property.If I am ONLY presenting the deal to the investor, meaning I am NOT buying the property myself or setting up any type of assignment, just "connecting" the investor to the property and running the numbers.