The building is massive in scale and appears to be built inside of the cliff-side behind it. In the front of the building, there is an extremely large parking lot that is typically empty. Despite its grand nature, the Desert Building does not play a pivotal role in any story missions, nor does any character recognize its existence. The unknown nature and giant size were a wake-up call for players of this game, and they started getting suspicious, believing it was hiding something sinister.
The first major set of sightings in this area occurred in the late 2000's when a comic known as the 4 A.M Series was published online. The comic included CJ with a specific set of clothes in front of the Desert Building, until a Red, beaten up Glendale pulls into the parking lot. An unknown figure, whose face is obscured due to the low quality of the camera used to photograph the TV, approaches CJ and the set of images end. The creator of the comic included step by step details of how he got the screenshots to happen and the comic is still a part of the modern Epsilon hunts today, as it included such things as the Red Truck and the Cane. The steps in the comic are believed to be one of many ways to join the Epsilon Cult.
Fans believe that the building is related to the Epsilon Cult, especially due to the comic. Eyewitnesses have been known to see members of the Cult congregating outside, as if in a celebration, and others have seen the Desert Building letting off a blue glow. There are little to no pieces of evidence for claims of Epsilon inhabiting the area, but their existence is still highly debated within the myth hunting community. A dirt road near the building has an unusually high amount of traffic, which fans have pointed out as strange because the building appears unused, but it is more than likely a vehicle spawn error. The site is located in Bone County, east of Arco del Oeste, northwest of the Cock Rock, and southwest of Valle Ocultado.
In The Introduction, a promotional video given in some copies of San Andreas, two members of the Leone Family can be seen burying a body near the Desert Building.
Due to the building's close proximity to Area 69, many players believe that the building is affiliated with the government or the United States military. If the player uses a map or building editor, such as MEd, to inspect the building, the building is referred to as the Resource Lab, possibly meant as a laboratory similar to those found within Area 69 itself.
One of the dots on the UFO Map mark the location of the Desert Building, which validates players' claims that something is happening in the area.
There is also a possibility that the building is an abandoned hardware store or office building, judging by its overall design and layout. It shares some aesthetic similarities to a hardware store adjacent to the aircraft scrapyard in Grand Theft Auto V.