I commend you for your greater attention to geographic detail than some authors and moviemakers I can think of.
Possibly you could contact the Washington, DC Chamber of Commerce for help in finding a currently abadoned building. I suspect that the Washington city government has a department, bureau, or agency that keeps track of abandoned buildings, so they might be able to help you find one. It is possible you could ask at websites about Washington DC, especially ones were residents might complain about eyesores in their neighborhoods.
Did you try going through the neighborhood with Google Maps and Street View looking for buildings which seem abandoned?
And if you can't find any real suitable abandoned buildings in your desired neighborhood, you can set your story in an alternate universe (it is my opinion that the vast majority of fiction happens in alternate universes) where a real building that was once abandoned but now is being rehabiliitated is still abandoned.
Or your can invent an imaginary abandoned building in that neighborhood.
Or you could find a still abandoned building in another part of Washington, DC and rewrite your story as little as possible to plausibly set that scene in that abandoned building in that partof the city.
And whatever you chose, you can pride yourself on being a lot more concerned with geographic and ohter accuracy than many writers and movie makers, some of whom got rich and successful. You are a lot closer to the kind of writer I prefer than perhaps the majority of writers.
A very few of the very many examples I have noticed follow.
I remember a science fiction short story published a few decades ago about a scientific detective type character, which had scenes set in Lancaster County, Pennsylvania.
The detective's office was in King of Prussia, PA, and he said that Lititz in Lancaster county was 60 miles east of King of Prussia. Sixty miles east of King of Prussia should be in New Jersey - according to Google Maps, near Howell Township and a few miles inland.
Lititz is about 50 miles west of King of Prussia. There was also an assay offic ein lititz. I associate assay offices with old west prospectors and ore samples. Would there be one in a modern small town like Lititz?
There was an episode in the sitcom Family Ties where Alex Keaton's girl friend was on a train and he tried to catch up with her. There was a scene in the train station waiting room at Lancaster, PA. And naturally it looked different than than the actual waiting room.
Since you are interested in Washington, DC, the science fiction film The Day The Earth Stood Still (1951) had a car chase there, where the streets used were mentioned. I wonder whether tracing the route on a map would be possible or if the streets and intersections aren't all real.
The goofs section for The Day The Earth Stood Still (1951) at IMDB says:
When Helen and Klaatu are going to the professor's, the army states that their cab is heading northwest on Connecticut at Columbia Rd. The cab then passes under the Dupont Circle underpass on Connecticut AV. The underpass is south of Columbia Rd, not north. Also, if the professor lives near the State Department, they are going in the wrong direction. The State Department offices are south of Columbia Rd.
The fat man running crying, "They landed in the Mall," is wrong. The Mall is a long relatively narrow strip of land stretching from the Capitol Building and the Washington Monument.Yet Klaatu sets his saucer down in a square field with the South Face of the White House clearly visible at the edge of frame. Furthermore, there are three baseball diamonds present: there are no baseball diamonds at that location.
And the noted television movie Welcome Home, Johnny Bristol had a scene set at the intersection of Vermont and Charles Streets, Philadelphia. It appears that Philadelphia has a Charles street, but no Vermont Street.
I once read that Frank Nugent, screenwriter of Fort Apache (1948) said that director John Ford had him read a bunch of books about the Apache Indian Wars and then told him to forget everying he read and write a good story.
Nugent remembered enough that all of the named Apaches in the film, Cochise, Geronimo, Diablo, Alchesy, and Satanta, were real people - but Satanta was actually a Kiowa.
But he certainly forgot a lot of geography. In the movie, Fort Grant and an Apache reservation are north of Fort Apache. Fort Apache was north of Fort Grant, and the northernmost Apache Reservatin in Arizona is the Fort Apache reservation.
In the movie Fort Apache is reached though a bunch of fictional places from the north, when it was actually reached from the south.
In one scene characters cross the Rio Bravo river from Arizona into Mexico. Rio Bravo is another name for Rio Grande, and the Rio Grande river is over a hundred mile from Arizona. And they cross the Rio Bravo at what looks a lot like the Grand Canyon, hundeds of miles north.
The actual Arizona-Mexico border is much flatter with valleys and low mountain ranges which are more north-south than east-west.
A Distant Trumpet (1964) was filmed hundreds of miles away in a differnt type of landscape, but the scene where where Apaches flee into Mexico and General Quaint halts his persuit at a not obvious border is much more realistic than Fort Apache (1948) with a misplaced Grand Canyon.
In Red River (1948) a 1850s wagon train to California passes close to the Red River of the South, the present border between Oklahoma and Texas - less than a day's ride from it. Even the southern trail to Califoria through New Mexico and Arizona passed one or two hundred miles north of the Red River, so the wagon train should have been lost and died of starvation before reaching Californa.
Three characters leave the wagon train and cross the Red River into Texas. According to movies, Texas was good only for cattle raising until oil was discovered. According to the movies, there aren't any farms in Texas, or cotton plantations whose owners made Texas join the Confederacy.
But in Red River (1948) the three travel hundreds of miles thorugh Texas, reaching the Rio Grande river, before they find a place good enough for their cattle ranch. Which makes you wonder what Texas was good for in Red River (1948) if good sites for cattle ranches were that hard to find.
In The Commancheros (1961) a riverboat takes several days to travel from Louisiana to Galvaston, Texas. There are no rivers from Louisiana to Galvaston, only the Gulf of Mexico. Nobody would dare take a riverboat acrsss the Gult of Mexico to Galvaston, where thousands of people were killed in a hurricane in 1900.
After arriving at the seaport of Galvaston, a seemingly short trip takes characters into an arid desert which looks too barren even for the cattle ranches it seems to have, and whch was actuallyy filmed hundreds of miles from Galvaston.
And even the latest western movies aren't much more accurate. In Hostiles (2017) a cavalry officer in 1892 is assigned the task of taking a Cheyenne warrior and family, presumably from a reservation in The Indian Territory (modern Oklahoma), to his home in Montana. On the way they meet a band of hostile Comanche warriors!
There weren't any hostile Comanche warriors in 1892. A date 20 years earlier in 1872, would make hostile Comanche warriors on the route north to Montana much more Likely.
And the logical route to take in 1892 would be to go to the nearest railroad station, take a train east, take another train north, and take a third train west to the closest station to their destination. That would avoid hundreds of miles of riding. Even in 20 years earlier, in 1872, with much fewer miles of railroad in the west, that would be the logical route to take.
These examples show that western movies move rivers, canyons, mountains, plains, deserts, forest, railroads, villages, towns, cities, forts, Indian tribes, and everything else around the map with no regard for actual geography.
And don't forget the 1968 movie inaccuately titled Krakatoa East of Java.
I once read an introduction by Isaac Asimov to a book by L.Sprague De Camp where Asimov praises De Camp's research for his historical fiction. But in Lest Darkness Fall (1939) a time traveler appears near the Pantheon in 530s Rome. Asking directions to the forum, he is told to take a specific street and then turn left at a specific intersection, when actually he should have been told to turn right. Arriving at the Foruma anyway, he notices that the columns have been removed from the temples in the forum. And as far as I can tell all the temple columns in the forum remaind standing in place for centuries afterwards.
And also see: https://writing.stackexchange.com/questions/54914/distorting-historical-facts-for-a-historical-fiction-story/54936#54936
I commend you for your greater attention to geographic detail.