In Steven Reddy's excellent Sketching Interiors class, he instructs us to use a series of India ink washes after our contour ink drawing (among other things). He makes drawing details easier by instructing us to draw foregrounds, middle ground, and then backgroun elements in that order with the freedom to edit out items as we choose. 

I took a photo from our recent trip to Paris and tried out his techniques. Here is the phase before adding color.  

Using this method really helps me to see values (lights and darks). But, I can't help but add watercolor.  

Grisaille refers to a painting done entirely in gray tones and was popular during the Renaissance. Have you tried it?