Abandoned photography comes in many forms. There are Photographers that go into empty houses key word is empty and take a snap shot of the rooms. I prefer places that remain full of things that were left behind decaying or layers of dust. Because of this these places are hard to come by because of the owners worrying about liability. You can gain access by booking a workshop with a group. I have done the workshop thing just to gain access to places I couldn't go any other way. Somewhere in-between this is places like Eastern State which is really a museum of sorts with restoration going on. These places are usually well kept and lack a lot of the things I look for when exploring. There are many things to photograph but you will have a lot more people to contend with. You are limited to your access to objects with do not enter or locked doors for employees only. You won't have to worry about getting caught trespassing because you pay a small fee and they let you take your photos. I went twice. The first time it was billed as a photographers tour and it was, too many. There was little to shoot with all the equipment and models. I then went back on a photography work shop that offered some access not open to the public. It also was too crowded because prisons weren't built for comfort. I got some photos but I don't think I would have done it knowing what I know now. I did get an advantage being in the building first because the mirror shot would be very difficult with the general public milling around. However, if you are just starting out a workshop, the right workshop is extremely helpful. Another thing about abandoned places is darkness. No one is paying the light bill anymore or people trash the places by doing scrapping. Before you go if you are fairly new to abandoned photography brush up on long exposure or what you need to know about it and a tripod is your best friend. You will need to trigger the camera in a way that you don't bump it. I have done a few blogs on what a work shop should be and It pays to do a little research because they are not all created equal.