A while ago I was approached by a friend who wanted a painting doing of her daughters house. I was very happy to oblige and she provided me with plenty of reference photo's and some very clear guidelines as to how she wanted the whole thing to look.
The painting is a combination of pen and watercolour. I do call it Pen and Wash but in my mind 'wash' implies loose transparent colours whereas this is more a pen drawing that's been coloured in with fairly strong colours.
Using pen has enabled me to add quite a lot of detail that I wouldn't normally include in a watercolour painting, like the house number set into the stained glass panel in the front door. Of course, these details aren't visible in small interent-based jpeg's.