Housetraining an older dog
You will probably need to set morning and evening feeding times. Previously the dog may not have had such an organized life schedule, so this could take time for adjustment. Don’t believe that old saying, ‘you can’t teach an old dog new tricks.” It’s not the age of the dog that matters - it’s the consistency of the owner.
If your dog came from an abusive home, even if is was just filled with shouting and hitting with paper for any accidents, then your efforts with house training an older dog may take longer. First you have to win the dog’s confidence and understand that he needs time to get comfortable in his new home.