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.  

Alternatively, something cosmic could happen, and Phoenix could become the place to be in the next few years:https://www.express.co.uk/news/science/1010638/cold-weather-forecast-big-freeze-solar-minimum-maximum-space-news

Unless you are in a high tech area or have a really modern property, I don't think tenants will like this. 

Well I wonder then if they even think about wet hair like you did or just go into hgtv mode and think the shower is so modern looking.

Not only do they have high CoC returns but they have good population growth, growing jobs and diverse and modern economies.

Plenty of properties have been rehabbed to modern building code.

I've also found that most of the multifamily properties are in need of a lot of repairs and/or modernizing to maximize rents.

The closest alternative would be to purchase a SFR and find roommates, or get incredibly lucky and find a property with multiple detached units already built on it (which in many cases will not be in compliance with modern zoning regulations).

Plant 51 features a modern combination of living spaces and outdoor ambiance that bring together stunning architecture and unique style.

Plant 51 features a modern combination of living spaces and outdoor ambiance that bring together stunning architecture and unique style. 2 bedroom , 2bathrooms . 1400 Sq Ft What made you interested in investing in this type of deal?