Rent is generally from 1k to 2k, usually much closer to 2k. I-house is great for the first semester since you have a cafeteria, and you'll eat with many of your classmates (assuming they also go to I-house). It is, as far as I know, the absolute closest you can live to Haas. However, it's about 2k a month, and super loud late at night if you're on one of the low floors (below 5th). A few people will get lucky and find something cheap on craigslist/airbnb, but they're generally apt hopping throughout the year or living pretty far. You really don't want to be spending hours on craiglist instead of studying. The program is extremely time consuming.
Many students also went to Manville, which they seemed to like. It's cheaper but fairly far, being all the way on Shattuck. Jackson on the other hand is pretty close and it's cheap, but I think you may have to share an apartment. The good thing is it will likely be with other MFEs.
I stayed at I-house for Spring and Summer and then found a cheap room via craigslist with an EE student. I happened to get lucky with the place on craigslist, and I'll be posting an ad through the program a bit down the road.
BTW, I'm a current MFE14.