In the New York area, two companies specialize in creating temporary separation walls for apartments--The Wall Company and Living Space,
Inc.. They provide exactly what we want. Here's a picture:
Unfortunately, we live in Palo Alto. I haven't been able to find someone who provides a similar service in the Northern California area. However, it seems almost certain that such a business already exists. Do any of you know where I might find something like this in the Bay Area?