Here is a side by side comparison of Silver and Gold package photos. Both use the same base image. The gold photos add extra layers which have been flashed with a powerful strobe light to add detail and texture. These layers are then composited into a combination of layers creating a whole greater than the sum of its parts.
A close inspection will reveal the subtle differences between the silver and gold images. Differences that could draw a client with discerning taste to be more interested in a property. Notice the windows between the silver and gold images. Also the evenness of the shadows and light.
Only the interior images have been flashed with light. The exterior images use a technique called High Dynamic Range or HDR. The difference between the Silver and Gold package here is less pronounced, but can make a difference.
More than twice the amount of work and time goes into the Gold package. In my humble opinion it is worthwhile for higher end properties, especially with furnishings or good views of the outdoors.