Here is my post-work technique: I render, go to Photoshop and drop the saturation, spike the contrast and print. Then I tape it to the window and trace or copy it by eye... then I paint in gouache. For some digital work I go to Photoshop and play with levels and noise and desat then burn with gradient maps and psedo-depth-of-field blurring for a photo look. I never use straight hyper-real renders except commercial work and I usually try to get the client to go with a digital watercolor, airbrush or oil done over a tracing... sometimes a scanned tracing done from a print.