NOT A TEACHER
1. I, too, love modification questions, so I am very eager to see what the teachers tell us.
2. I only want to share some thoughts, not answers.
3. I think that it would be more "natural" to express that idea in a sentence something like:
"It would be unwise for us to move to a larger house now."
a. I am 99.99% sure that "for us" modifies "unwise." It answers the question "for whom?"
i. We would be unwise (now) to move to a larger house.
ii. We would be unwise to move to a larger house (now).
iii. (Now) we would be unwise to move to a larger house.
4. I dare not comment on what "now" in your original sentence modifies. We will have to wait for a teacher's answer.
HAVE A NICE DAY!
Student or Learner