So when they arrive on our site they see mainly mid-century modern homes from the mid 1940's to about the early 1970's particularly with the post and beam construction designs by, Alfred Beadle, Ralph Haver, Schribner, Killingsworth, Blain Drake and others.

The contemporary homes and modern homes have much in common, especially when modern mid-century homes are remodeled to accommodate the current living standards. Both are attractive for very similar reasons, but their design language is somewhat different so I did some more digging and came up with the following distinctions of the two terms, but the phrases are open to interpretation and have many shades of meaning and this creates some unfortunate confusion.

The difference between modern architecture and contemporary architecture styles are many. Modern architecture styles feature the use of materials in a rational way. Contemporary styles of architecture are the evolution of modern architecture, representing today’s styles and design concepts. The terms modern and contemporary architecture are used interchangeably but are not the same.

It's not so much that modern does not have a clear definition, it's that there is no word to describe contemporary homes other then 'contemporary' which in itself has a loose meaning that can be applied to stucco homes (though it's not) or glass covered houses and so on, but then what comes after contemporary?: so modern has kind of taken on a new meaning and all this truly confuses the situation. In other words it's easier to define 'modern' then it is to define 'contemporary' or an alternative to what some call 'modern - contemporary' architecture.

Modern

Modern Architecture is linked to certain genre and time period which has passed. Some key architects of that period include Le Corbusier or very early Frank Lloyd Wright followed by many of his students, some of whom were named above.

Modern is often used for foreword thinking form, but that is wrong, modern is in the past, a by gone era (mid 1940's to early 1970's) design philosophy by now surpassed.  Better yet take a look at modern homes for sale.

"Modern architecture is usually characterized by:

• an adoption of the principle that the materials and functional requirements determine the result
• an adoption of the machine aesthetic
• an emphasis of horizontal and vertical lines
• a creation of ornament using the structure and theme of the building, or a rejection of ornamentation.
• a simplification of form and elimination of "unnecessary detail"
• an adoption of expressed structure
• Form follows function"  (Modernism on wikipedia)
  

Then there are combinations of the words, but I think there is really more confusion then there needs to be.  A simple way to discern the two is to think of modern as a term similar to any design standard of a particular time which may be still used, but is more history then anything ground-breaking while contemporary for lack of a better term is used to describe homes that have evolved from the modern vein, but don't include anything rooted in classical architectural styles.

Contemporary

Contemporary design styles tries to transcends form and function, incorporating natural elements and integrating the design with the environment to create a symbiotic relationship to a letter or greater extent.  Think Frank Gehry of locally Will Bruder, DeBartolo Architects and materials like steel, glass, lots of glass, and organic forms.  It is a term applied to more recently built structures since about the 1980's  See" contemporary homes for sale to get a better idea.

Modern Phoenix uses these terms, "classic midcentury modern domestic architecture" and "modern contemporary designs"  Do these work better?

You can find both types of architecture and homes for sale featured on two separate pages here at Phoenix Market Trends: the Mid-Century Modern page and the Contemporary Home page.