If crime (i. e. robberies) doesn't bother you, Eastside (west of campus) is cheap and has shopping along University Ave. The Iowa/Blaine/Linden area often has apartments available, it's techincally not in Eastside, but it's close and there are robberies there pretty often. There's also the area east of campus, which is somewhat safer, but more residential. As far as I know, it only has one grocery store: Goodwin's organic, which is probably relatively expensive. Canyon Crest, south of campus, is a nicer area, with shopping (canyon crest town center), but somewhat more expensive. It's a long walk, because the agricultural experiment station is south of campus, and canyon crest is south of that, but it is bikeable and there's a shuttle too (look up RTA bus route 51). I don't think you'll have much of a problem finding an apartment a few weeks before the start of the quarter, esp. if you aren't looking for anything particularly nice. From my experience, there aren't many studio apts in Riverside. You can get a 1 bedroom apt for ~$700/month. With roommates, you can get a room for ~$400-500.