The most important factor is the price. I can't afford to spend more than $10 or $15 on each item. If need be, I'll shop only sales and clearance items.
Does anyone know of a store or stores like this?
Most Helpful Girl
H&M, Forever 21. If you're going for something more sophisticated, I'd go with H&M over Forever 21, because imo, it's better quality (and as a result, a little bit more expensive, but not much - still really affordable!) but it has more clothes that cater to people in their 20s (rather than just in their teens), and has a lot of good basics.
Zara also has what you're looking for, but only buy from there when it's on sale, otherwise it's pretty expensive. I got a bunch of really nice shirts from there for like $15, though, when they were having a sale. And I don't know if there are any near you, but outlet malls have really good deals, even on designer clothes.