Collage can be used to add texture rather than pattern or colour to your work, so I did this naive street scene to demonstrate a possibility.
First I cut out shapes from mountboard and corrugated card and stuck them onto a further piece of board with PVA glue.
Having let them dry, I put on two coats of white watercolour ground and let it dry overnight. Grabbing a fine Uniball pen (make sure the ink is waterproof), I started drawing in the town houses:
And continued along the road, adding in little architectural features:
Then, it is simply a matter of washing over with watercolour and once dry perhaps adding a few more details, such as darkening some windows.
Finally, it will need a fixative once dry, as the paint is pretty vulnerable on the watercolour ground.
It would be fun to do something like this for a local road – flattening and simplifying the perspective of each house, or perhaps fishermen’s cottages in a harbour…. If you like this naive style, take a look at the work of Julie Adlard – she uses clay collage on canvas and acrylic paint: https://julieadlard.co.uk