I have been working over 8 years in the 3D architectural rendering field. I'd love to share a little about what makes an excellent rendering experience. The first thing coming into mind tends to be a team's skill. Then, what's the second thing on top of that? I would say PATIENCE. Most of the time, patience could play a more vital role than a team's skill. Preparations such as study on the context/building programs/furniture style/entourage selections are very essential. A quality rendering would focus not only on the building/space itself, but how it relates to the existing environment, and how well this building/space is used. This may need huge patience! Anyway, take pains, be perfect.