As part of my job I am the staff photographer. I always clearly communicate the portrait dress code, but sometimes people either don't listen, refuse to comply, or as in a couple of cases, don't have the required attire in their wardrobe. Here's how I deal with that.
First, I thank my lucky stars that there are people who do comply. It gives me plenty of source material for the project. Then, I simply do a wardrobe transplant.
Here the gentleman to the left did not bring a jacket for the shoot. Now, we have some spare jackets lying around, but this guy's a stout dude--his neck's like a tree trunk, for crying out loud. I have nothing that will fit him. The other problem complicating things was that he is a remote field employee. He hardly ever visits the home office--maybe once a year. There was no way to reschedule a reshoot; I had to get his photo this time or there was no telling how long it would be before the opportunity presented itself again.
Lucky for me I had plenty of source photos to comb through and look for a jacket to match his ensemble. I chose one from the photo of another gentleman with broader-than-normal shoulders, but I still had to do a fair bit of transforming to make it match the contours of the first man. Then just for the heck of it I decided to lighten the color a tad to more of a charcoal.
Anyway, this wasn't my first time at the rodeo. In doing employee photos I've also had to composite up to as many as four shots into one final product, add a necktie, tighten a necktie, remove wrinkles (from clothing and faces), color hair, whiten teeth, add color to dead-looking, sunless, pale faces, remove cold sores and other blemishes... You name it. That's part of semi-professional portrait photography. You have to hope for the best but expect the worst and be prepared to address it.