Hello mikecu.
Welcome to BYC.
Whoever let you have those chickens is not a reputable breeder in any sense of the word I understand.
Apart from the toenails which should get worn down if the chickens are kept in reasonable conditions the chicken in the picture has scaly leg mite.
You can treat scaly leg mite with Vasaline (Petroleom Jelly) and I mix the Vasaline with Betadine (Vas 75% Bet 25%) the Betadine helps disinfect and is anti fungal.
Smother the legs and feet in this mixture for three nights; easiest to do after the chickens have roosted, and repeat again after two weeks.
Given the conditon of the feet, I would check the chicken for mites and lice.