If you're unemployed, you won't need to pay 2 grand/month for someone else to watch your children, and you don't have to pay San Francisco rents if you're not working there.
I'm interested in how you expect someone to attend school/retrain without childcare. You can't generally bring your kids to class with you.
Your solution to childcare is permanent unemployment?
This is Denver rent actually, and increasingly most urban centers.
I don't think "just give up your existing community and move" is a viable option. That defeats the whole point since at that point the retraining isn't allowing you to maintain your quality of life.