Hi there, I'm hoping I can get some help asap 
We have a neighbor who has four rhode island hens and she is done with them and wants to get rid of them. They are about 2 years old and all but one has missing back butt feathers. One she said is brooding and does nothing but lay on fake eggs all day in her nesting box (she put them out there) and she said in the entire time she's been an adult her feathers on her butt are gone completely with just skin and it hasn't grown back. They are not free range, they are living in an enclosure about 10x10 feet wide with their house in it as well. She has never treated them for worms, etc. and they get hen scratch everyday twice a day and that's all, no pellets, etc. Could their feather loss be because of stress and lack of space? Or do you think it might be that they have mites, etc. I am worried about bringing these chickens into our backyard in a brand new coop, etc. if they are infested with stuff but she seemed to just think they are pecking at each other and I'm wondering if that isn't the truth because they are bored but then why is just one perfectly fine looking? Sorry for all the questions, these will be my first chickens and I really want to make sure that we are successful with them from day one.

We have a neighbor who has four rhode island hens and she is done with them and wants to get rid of them. They are about 2 years old and all but one has missing back butt feathers. One she said is brooding and does nothing but lay on fake eggs all day in her nesting box (she put them out there) and she said in the entire time she's been an adult her feathers on her butt are gone completely with just skin and it hasn't grown back. They are not free range, they are living in an enclosure about 10x10 feet wide with their house in it as well. She has never treated them for worms, etc. and they get hen scratch everyday twice a day and that's all, no pellets, etc. Could their feather loss be because of stress and lack of space? Or do you think it might be that they have mites, etc. I am worried about bringing these chickens into our backyard in a brand new coop, etc. if they are infested with stuff but she seemed to just think they are pecking at each other and I'm wondering if that isn't the truth because they are bored but then why is just one perfectly fine looking? Sorry for all the questions, these will be my first chickens and I really want to make sure that we are successful with them from day one.
However, I wouldn't be surprised if it were mites, which I've been told isn't that big of a deal and can be easily remedied? Please give me suggestions if you have any. I couldn't get a photo because I felt like that would have been weird to ask since I don't know her personally and stuff. I talked to someone local and they said they definitely think it's mites, lack of space for all four of them and of course that they aren't being fed properly for laying 2/3 eggs a day, there is no protein hardly at all in their diet. They would be transferred to a brand new coop and 1/2 acre of open range land with grass (where I live) so if we do take them on it's a MUCH bigger and much better situation for them. I guess now I just don't want lice. Hahahah. Does it look the same as mites?! All of them lay eggs except the broody one. And one has no butt feathers, the broody one, and two of them have sad looking tails and one has no issues at all. All same age and all raised as chicks.