From what i can see looks like a bunch of empty oxygen bottles and a Oxygen concentrator for people with COPD or lung problems. Then a propane bottle i think.

The bigger ones look medical and could be liquid oxygen which could be for COPD care or something medical that you need oxygen with as they have those plastic tops which regulate and i think also warm the oxygen so its okay to use for breathing. Similar tank

Its all medical stuff in my opinion, i would guess someone suffering from COPD as you get through a lot of oxygen and as the other smaller bottles of gaseous oxygen and the machine are left outside it may mean they have had to increase the amount of oxygen so could explain why there are so many, as you usually do this as the COPD gets worse and your struggling to breath.

A family member had COPD and they had a lot of the same equipment the smaller oxygen bottles are used when out and about and then the concentrator is used in the house with a long tube on it so they can walk about but with oxygen mask on, i think there is a upper limit of what a Oxygen concentrator can produce so if you need higher amount of oxygen you might need to use those bigger liquid oxygen ones.

Not sure about why they have the propane looking bottle though as generally you dont want to mix them as oxygen makes everything much much easier to burn.