Below is Omar Mateen's rented minivan (as the police claim) parked the shorter of two blue canopies. Above the image, from where I borrowed it, it says: ".@wftv reports this is the vehicle belonging to #Pulse shooter, Omar Mateen, parked outside the club".
http://www.tribwatch.com/photos/orlandoVan.jpg If one knows the make and year of Mateen's van, one can discover its length to the inch. Searching, I may have found it to be a Dodge Caravan (not Grand Caravan); the rims definitely match a 2014, 2015 or 2016 Caravan. Here's Google's page for the 2014 model.
As I don't know for certain what make and year Mateen's rented vehicle is, and as no one online seems to have told it (when I searched for it, anyway), I've decided to do a measurement of the building using the rim size of the van. This method looks accurate to 95 percent. It can be assumed with high certainty that it's a 15-inch rim. I have measured a 15-inch rim on my own vehicle to find that it measures 16 inches in diameter. When the image above is expanded so that the rim measures just under 29/32 of an inch (2.3 centimeters) on my screen, the canopy measures 6 5/16 inches (16 centimeters) wide. To find 29/32 in decimals, divide 1 by 32 and multiply by 29 = .906 of an inch. The width of the canopy in decimals is 6.313 inches.
Next, find how many rim diameters fits across the width of the canopy. It's easy: 6.313 divided by .906 = 6.97 rims. This means we have reliably found the width of the canopy to be 6.97 times 16 inches = 111.5 inches = 9.29 feet. This canopy happens to be side-by-side with the Pulse building's roof on a satellite image here: http://www.tribwatch.com/photos/orlandoRoofV iew.jpg
In the image below, the canopies are side-by-side, as they are in the image above, whereas the canopies are end-to-end in the Mateen-van image. It becomes clear that the canopy measured above is the shorter one where they show side-by-side. http://www.tribwatch.com/photos/orlandoAlleyView.jpg
I'm going to do the building measurement (outsider-to-outside walls) using the Roof-View image rather than the one directly above. Your screen sizes are not going to be exactly like mine, so just plug your own measurements (on any-size image you prefer, larger ones gives better accuracy) to this math. On my screen, the width of the canopy (in the van image) is 2.6 centimeters while the length of the roof is 19.1 centimeters, meaning that the roof is 7.35 times longer than the width of the canopy:
wherefore the approximate building length
= 7.35 x 9.29 feet = 68.3 feet.
(The larger the rim in reality, the longer the roof length.)
The width of the rear-most part of the building (14.8 centimeters on my screen) is 5.69 times the width of the canopy. The roof there is therefore 5.69 x 9.29 = 52.9 feet (with a 15-inch rim measuring 16 inches visibly).
The width of the canopy is .65 times the length of the Mateen minivan. To find the length of the vehicle, do this math: 1 / .65 x 9.29 feet = 14.3 feet.
I have found some disinformation online as per the length of a Dodge Caravan; don't mistaken it for a Dodge Grand Caravan. I don't know for sure that Mateen's vehicle is a Caravan. There also seems to be disinformation on the square footage of the Pulse building, both floors.