My fiance remembers fondly the burgers at the GW staple, Lindy's. It's a dive, but definitely affordable and offers a wide variety of burgers.
Burger with Swiss cheese, bacon and mushrooms.
American Bacon Cheeseburger with fries
The Yelpers were right, service is a bit on the slow side, but our waitress was really pleasant and the griddled burgers were good. I liked that they offer two sizes, with one patty or two patties, and a wide variety of toppings. Most importantly, my fiance enjoyed his reintroduction to Lindy's after a number of years.