There's unfortunately not a lot of readily accessible and reliable statistics on camera ownership in the 19th and early 20th century. Where I can provide an answer is the camera that made photography available to the general public: the Kodak.

In the 19th century when photography was invented, it required large, heavy cameras that usually used large plates with a light-sensitive emulsion of silver salt as the "film" inside. These were awkward and difficult to use and carry around, and both the cameras and plates were correspondingly rather expensive. The only people who really practiced photography were professional photographers who did their own photo development and made the plates themselves with chemicals. Glass plates continued to be used into the early 21st century for electron microscopes and space photography due to their extreme optical quality.

In 1885, George Eastman released the first commercially available flexible film of light-sensitive chemical on a paper base. This would be refined in 1889 into transparent plastic film made of nitrocellulose. In 1888, Eastman began selling a camera called the Kodak.

The Kodak was a very small camera that cost $25 (equivalent to about $700 today, so more like buying a good DSLR than a cheap disposable camera). It was pre-loaded with 100 shots' worth of film, with a round frame rather than square to make it easier for the consumer to avoid tilted shots. You would look through a viewfinder in the top to line up the shot, pull a string to prime the camera, then press a button to take a photo. Wind to the next frame (indicated by a spinning pointer) and you were good for another one. When you were done, you would pay $10 (equivalent to about $280 today) to send the camera back to the Eastman Dry Plate & Film Company in Rochester, NY to have the photos developed. They would return your 100 photos with a freshly reloaded camera.

While this is fantastically expensive and inconvenient compared to modern day, it was revolutionary. Now any middle or upper-class family who could save up $25 could have photography at their fingertips. As film and its development got cheaper and the box camera was refined, its cost would drop lower and lower until the Kodak No. 2 Brownie released in 1900 cost only a dollar (about $25-27 today). By the turn of the 20th century, snapshot photography was a thing everyone could get.