You may find that you agree on some things. If you can discuss your disagreements, you will probably get ideas for your journal. Sketches are very appropriate to help illustrate your recollections and your ideas for changes. Any two houses seen are going to have similarities and differences. Try making some comparisons.
Sketches can illustrate a comparison style.
It is creative to make a list of possible lists that could be made about a house. Once the lists are made, it will be easier to think of things to write about. I often use my sketches as a list of visual ideas. I hope this has been helpful. Don't hesitate to communicate you ideas, questions, and concerns.