As you can see from the title, this image is quite a few renders on from the original. I have added a fence with arches over the pathways. I don't think that toadstool houses have water plumbed in, so I created the well, to save the occupants a long trek down to the nearest stream.

I extended the ground right out of the picture and added a few hills in the background.

For this render I used a stock photograph as the background. This actually blends very well on the right hand side, but sticks out a bit on the left, it probably needed an amber coloured light over the left hand hill, to make the colour there match the background.