I am used to working with tight yet realistic deadlines. My usual workflow is as follows:
-Provide a greyscale image/ images to show camera angles, basic geometry and illumination.
-Provide low-res image/ images with texture/ materials applied and basic postproduction.
-Provide final high-res image/ images with final mark-ups, full postproduction, people (if necessary) and final effects and artistic touches.
This workflow may vary depending on type of project, deadline, budget and client specifications and requirements.