My oldest started grad school this fall in an area that is in the top 5 of the USNWR list for highest cost of living areas in the US and she has been extremely fortunate to have a subsidized housing guarantee for on campus for up to 6 years and is currently paying $1125 a month for a 2 bedroom apartment that she shares with a roommate. She is lucky that there are also no utilities, cable or WIFI expenses because the rent is 45% of her grad school income. She has no other expenses besides food (no undergrad loans) which allows her to contribute the max towards a Roth IRA each month.
We looked at off-campus housing to see what was in the area, but the cheapest we could find for a single was $2100 for a 400sf studio. 1Br apartments were from $2400-$3500, 2Br apartments were $3,200-$6,000 and we saw 3Br apartments/houses for rent range from $6,000-$12,000 close to her campus.