<prompt> Human: So I have seen various posts saying that monthly rent should not be more than 30 of your take home pay, or more than 140th of your annual income. My question is does this measurement really hold when you are renting in a expensive area such as San Fransisco or San Jose?  <response>: Theoretically yes, because salaries are higher in these cities. Be prepared to have a lot less living space or live in an inconvenient location.30 is more a guideline than a rule. It can go right out the window in cities with unusually high costs of living, like NYC or SF. 