Hi @Marshall Secord, assuming you use a good primer meant for painting masonry exteriors, you should be able to cover the 300 sq ft with the manufacturers stated coverage rate (usually something like 1 gallon covers 350ish sq ft).  

@John VanharaIs the building a steel structure underneath the masonry? 

Same could go for much of the masonry and stonework of the past compared to now.

Single family homes vs garden apartments vs high rise apartments will all have different ratios and within those classes, will all have different results in different states.It is not possible to get the number you are looking for as an accurate across the board of all investment classes for cap ex or repairs/maintenance.That said, here is a blurb copied form the NAA (National Apartment Association) which puts out data on operating and cap ex expenses for apartments of garden style and high rise: “Capital expenditures, which can include anything from concrete and masonry work to amenity upgrades to extensive rehabs of some units or a clubhouse, has steadily increased since 2010 when measured against GPR.

This usually includes but is not limited to PLUMBING, flooring, landscape, utility lines and masonry.

Land clearing, exterior/interior paint, flooring, appliances, kitchen remodel, and some masonry work.

Most early row homes were constructed using 8” masonry party walls with 16” rubble foundations.

This usually includes but is not limited to PLUMBING, flooring, landscape, utility lines and masonry.

They finished the roof and we found a masonry company to come out and tear down the old chimney and put up a new one, (with the help of homeowners insurance). 

If it's an interior chase you can use double walled flue piping a masonry chimney isnt needed with double walled "b" vent.