Eplans.com is a website that sells blueprints for houses.
This might not seem that helpful but if you want a characters house you can make selections based on what sort of house you want them to live in.
Then browse through the results and find the house you want. Then you can view the blueprints and have a room layout for that house, which can help with visualising the space they live in.
It makes describing generic homes so much easier.