The Kilkare Inn was still there in 1924, and offering breakfast from 8 to 10:30 and lunch from noon to 2. Located at 813 Vermont Ave. NW, now the location of the Export - Import Bank of the US.

It's of note how much food prices have outpaced inflation. 20 cents is $3.52 today. You'd be hard pressed to get two sandwiches, a sweet, and fruit for $3.52 from a food truck these days.

From the want ads of the Washington Times, June 29, 1919:

"BOYS over 16 years old, neat appearance to sell Loeffler's Liberty Lunch; salary and commission; hours, from 6:30 a. m. until 2. p. m. Apply at once, 544 Penna. ave. N. W."

Severine G. Leoffler, 1887-1947. Obituary

Interesting guy. He had a number of business, ending up owning or leasing a dozen golf courses, though not a player himself. He came from Pittsburgh originally (excerpt):

"He came to Washington with $300. The first thing he was sell safety pins to school children, giving jack-knives as incentives. School authorities put a stop to that so he went into the ice cream business. He sold the first roller ice cream cone here. He sold that business for $20,000 and then sold box lunches - two sandwiches, a piece of fruit and freshly baked pastry, all for 10 cents. He sold that business for $100,000 and the guy who bought it went broke in six months."

The resourceful Leoffler broadened his horizons. He went back into the box lunch business during World War I, selling "Leoffler's Liberty Lunches" to government workers for 20 cents. But sometimes he got too ambitious. He decided to come out with square doughnuts and spent a fortune on machinery. He went broke. The public preferred the round dough out.

His son died in 2014, evidently keeping the golf course business going. Obituary

At one time if you lived in one state and worked in another a registration plate for each state was required, as displayed on the above Ford. The oil lamp was original to the car, but an extra lamp was added to shine on the upper plate. This nonsense was stopped eventually.

Prior to 1924, motorists in the Washington region were obliged to register autos in all three jurisdictions (DC, Maryland and Virginia) prior to crossing the state lines. There were stiff fines and the law was always on the lookout for violators. Obviously it was difficult to display three plates on the same auto and the practice was discontinued.

Back in 2008, in the linked post, Dave asks in response to a poster wondering about a menu in the box: "Looking for volunteers to go back in time and peek in the box. Anyone?"

Wonder no more! According to the July 1, 1919 Business Digest and Investment Weekly, we have this item:

— Lunch Boxes

[S. G. Leoffler, System, Oct '19 p 644. 600 words. 1 illus]

Mr. Leoffler is the inventor of the "Liberty Lunch," which came in neat pasteboard boxes labeled "The Noon Time Friend" and saved Washington war-workers from a nerve-racking fight at overcrowded restaurants. The lunch contained two sandwiches in waxed paper, a sweet of some kind, and fruit. There were chicken sandwiches, raisin and nut sandwiches, Spanish pickle sandwiches, olive sandwiches, all sorts of sandwiches. But there was a little element of surprise every day, something a little different. Sometimes Mary Ann found a quarter of an old fashioned mince pie that reminded her of Thanksgiving, sometimes a slab of brown gingerbread. The company now has 130 employees and sells 10,000 lunches every week day. Six big motor trucks are used to deliver the lunches.

10,000 box lunches every day? That's a lot of lunches.