I think I found my friendly neighborhood cheap Chinese restaurant! (FYI: The sign on the awning says China Star, but the menu says Yen's and they say Yen's when they pick up the phone. Not sure of the reason for the discrepancy.)
The previous tenant of my apartment left the menu lying around, and last night we were desperate for dinner so we decided to check them out. Two vegetable spring rolls and two entrees cost less than $20 and were ready to pick up in 10 minutes. (Delivery would have taken 40 minutes even though we live half a mile away.) My boyfriend picked up the food and said the place seemed very clean.
The spring rolls were good and crispy. The vegetable fried rice had more than the requisite peas and carrots - there were mushrooms, corn, and even zucchini, which I don't think I've ever had in Chinese food but it was pretty good. The Mongolian beef was not just a pile of beef - there were plenty of onions and green onions to add color and texture. Portion sizes were more than adequate and we both had leftovers.
The best part is the price. The only entrees over $10 are the ones with seafood. All of the lunches (with rice and soup) are under $5! (Except for the ones with shrimp, which are $5.25 - still a good deal if you ask me.)
I would definitely recommend Yen's if you live in the neighborhood - it looks shady from the outside but I thought the food was better than Silk Pagoda's.