I feel this is a pretty simple process should take anywhere from 10-15 minutes to maybe an hour or 2 depending if there is polishing and if you get under the car as well.
I had a friend come by to get his engine bay cleaned up before he takes it in to get appraised for trade in....
Take a look:
Hey guys thought I would share this...
2000 S4 Engine Detail
Products used:
P21S Auto wash
Boar's Hair wheel brush
Adam's In and out
Adam's Foam applicator pad
Adam's VRT
Before:

After: