It’s true.  There are some sacred rules that shall not be broken.  Verticals must be vertical.  Horizontal lines must be horizontal.  If you go for that one point perspective… you better not miss, its better to not even look like you were trying for it than to be a little bit off.  Whites should really be white.  Shadows should only be where shadows should naturally fall.  Mirrors are portals to the land of the damned and will suck your soul out through your eyes.  Trust me.  They are evil and can not be trusted.  In even the dirtiest house there will be paintings that are so incredibly clean they reflect EVERY little photon that strikes them, seemingly amplified and into your lens.  
You are no longer a “civilian”, you can not look at houses on the local MLS, or pass the time waiting for an order of food looking at one of those realtor magazines.  You don’t even know what the houses look like.  But you do know that the verticals were off in that one picture.  You know that the overcooked, lazy HDR made the ceiling joints look like they are damaged by smoke.  That someone… someone peed around every single light fixture.  How else do you explain those yellow stains on the ceiling?  And why are the windows greenish and purple and blue?  
But… but is the house nice?  I don’t know!  Look at these pictures!

I have to put my hands in my pockets because my fingers are fidgeting and making all the little gestures they would be if I were sitting over my computer… fixing ALL OF IT.
Oh, and forget watching TV.  Just forget it.  You’re watching a show, the characters are having a deep, heartfelt moment…and you don’t even know who’s on the screen.  But you know, oh YOU KNOW, that the camera isn’t level – LOOK AT THOSE CROOKED VERTICALS!  And the white balance??? How hard is it to level a camera for crying out loud, on a multimillion-dollar Hollywood production?  This is unwatchable… my eyes hurt.  My head hurts.  I want to turn the TV on its side.  
And then there is that one picture, you know the one?  From the lovely historical home?  The one that’s a 120 years old and you loved it to bits, but oh my goodness… Nothing is straight in those houses… you see… they settle… over the centuries… some beams are a little less than horizontal.  Some walls… a little less than vertical.  And you used to love it.  It was “character”, it gave those special, beautiful houses heart, soul!  But now you just sit there with a Rubik’s cube of an image… Trying to make it all straight and you’re ready to scream…
Eventually, in the dark, with a computer screen burnt into your optic nerves, you rock gently, back and forth like Kurtz in the Heart of Darkness… and those brave enough to come close can hear a horse whisper escaping your parched lips:

“The Verticals… The… Ver..ti…cals!!!!!!!!”

Maybe it's a bit of a pompous title, maybe it sounds a touch pretentious - neither of those things could be further from my intent. That said, this is going to be a bit of an off-topic post, not directly tied to commercial photography per se, but I hope that by the end of it I will manage to ramble and meander my way to something resembling a conclusion and more importantly, a connection.
Photography, when done right, is an art form.  It is a form of expression, it takes skill, and talent, and most importantly vision. As photographers, we all start out from that lofty place, but I fear many of us tend to lose our way. This job is routine, that shoot doesn't pay enough, when it's a higher profile shoot I will go that extra distance but for now this will do... I think we all get mired in this kind of thinking regardless of the profession, regardless of what trade we ply. And it's wrong.  It's just backwards if you ask me.  
I believe that a true professional should treat every job with the same dedication, attention to detail and creative zeal.  There is an old saying: even a broken clock is right twice a day - what sets a professional apart is that they deliver results consistently, every time.  That they bring the same preparation and effort to every job, that they wouldn't want to be associated with anything less, and that their clients can rest assured they are getting the best possible value for their hard-earned cash.  And yes, when it comes to photography, be it for real estate or for the commercial needs of your business, I believe the same should be true.  Anyone can point a camera and push a button - you should expect far more from your professional photographer! And that "something more" should be readily apparent when you see the pictures they made for you.
Let me reference a couple of examples.  Lets momentarily remove the "commercial" aspect from our discussion.  Lets just talk about art for the sake of art.  
Anyone can go to their local Wally Mart or the Home Despot in their town or city and buy a framed "photograph" to hang on their wall.  It may even be a pretty enough picture, and may even pass the "50/50" rule, meaning it looks good 50% of the time, from 50 feet away... Just as it does in countless motel rooms and office lobbies across the land. The photographer who made the photo has little or nothing to do with the final product, no human touch, no nuance has been put into the making of the actual piece you are going to hang on your wall.  At best, it will be neutral and inoffensive, at worst it will look cheap and tacky.
On the other, polar opposite of that spectrum are real photographs, made by real artists.  Crafted by hand, each one printed individually in sweat and toil, sometimes after days of making "working prints" to establish the exact exposure, the dodging and burning needed in specific areas to bring the subject into the exact light pre-visualized by the artist.  No two are exactly the same, no one can make an exact copy by clicking a mouse button and letting their ink-jet printer do the rest.  
Take my friend Chris Baczynski of Silver Soul Photo as an example. A consummate artist and true master of an increasingly rare medium, he creates beautiful photographs on film.  His prints, both black and white and colour, are made by hand in a traditional dark room, and are absolutely striking. Each one is unique, each one has a little bit of his soul trapped in its grains of silver.  When you hang one of his prints on your wall, you know you are in possession of a one-of-a-kind piece of his life, captured in that photograph just for you. Even another print from the exact same negative will never be exactly the same, as the artist always improvises in the dark room, much like a jazz musician playing a solo. It may be the same song, but if you go to see the show ten times, you will be treated to ten different interpretations.  The advantage of a photograph is the fact that you get to keep that moment, and travel back to it every time you look at it.  
But lets say photography is just not your thing, sure you may (I would hope, as a meagre shutter jockey, at your service) appreciate it, find it useful and hopefully see its value, but you're just not that into hanging it on your wall.  It's ok, "some folks likes pork chops and some folks likes ham hocks, some folks likes vegetable stew", as the song goes.  The same goes for paintings.  I understand that here the issue gets a little bit muddied, as many "famous" painters are simply out of reach for the vast majority of the population.  Only a very small portion of us will ever hang a Picasso in our sitting room, or admire a Vermeer in the privacy and comfort of our own home.  And I certainly understand the appeal of the image, the beauty of some famous works which leads us to choosing a reproduction over nothing at all.  I get it.  But so many of us will go to one of the above mentioned "big box" stores and buy "prints" of paintings that quite frankly... have nothing to say, are mediocre by design, and their only claim to fame is that they were judged not to upset a vast majority of the population. You buy one of these things, printed in some industrial print house, most likely by under-paid, border line slave-labour in a far away land. OK, I don't want to drift off into politics, socio-economics and the like - but I will say, real living, breathing, creative, passionate individuals walk among us.  You may see them every day and not even know it.  Talented people who toil to produce real beauty out of a calling, a passion for their work, a desire to make our world a more beautiful place, a need to express something real, something profound and enrich our lives by doing so.

I will use an example of another friend of mine, Aga Niemiec, an Ottawa, Ontario based artist.  If you had to label her work I guess you would have to say modern realism and abstract impressionism.  She works mainly with oils, but I know she is quite adept at other mediums as well.  You can even commission a portrait! How regal is that, huh?  But really, none of that matters - what matters is that for really not much more than a quality, mass produced chain-store print, you will have on your wall, forever, for generations to come, a real piece of art.  Each brush stroke made by a human hand, never to be repeated, unique, individual, beautiful in a way that only a piece of someone's creative soul can be.  I can assure you, there is no chain motel or national brand hotel, or walk-in clinic that will have the same image hanging in it's lobby.  You can't buy it at the beds, baths, or whatever is beyond... On a tangent, I always found the name of that store somewhat creepy.  What do they mean by "beyond"?  Do I want to know? But I digress.
The fact is, weather its an original photograph or a painting, I would argue that each one is a better deal than the mass produced "equivalent" (using the term very, very loosely...).  I would stand firmly behind the statement that whatever the cost of an original work of art, it is but a small portion of its real value.  Whereas that thing you bought from the monster store... well... I would say you overpaid, regardless of how low the price.  It's a commodity.  A simple wall covering appliance if you will.  Its price is roughly four times its cost to produce, and those are the only factors in that equation.
I guess we are getting to that time when I should start making a point, aren't we?
Do you want your business represented by that mass produced big-box store trinket?  Or by a work of an individual who leaves a little piece of him or herself in each thing they do?  Do you think your business deserves a tired piece of stock photography for its website?  Do you think your lobby is best served by an odds-and-ends sale piece?  
I would put forth, for your consideration, that no.  It is not.  That no, you do not want that.  In fact, I believe you should strive for the direct polar opposite.  Unique work, just for you, from someone who pours their heart and soul into every project they undertake.  Find someone who has an insatiable need to do every single job to the best of their ability, who thinks every thing they do is a calling card, a reflection of them.  I don't care if it's the guy fixing your car, remodelling your kitchen, or photographing your business.  You deserve the best, and your clients will see the difference.  You will stand out above the crowd because the people you chose to work with would have nothing else associated with their names.
And buy some art for your home, your office. Something real.  Something with a soul, a message, a little bit of someone's irreplaceable spirit forever contained within it.  It will make you just a little bit happier every time you look at it.  
That, I think, is the tip of the iceberg of the importance of art.