When adopting a mature dog please be mindful that a lot of patience will be required.  It takes at least three days for the dog to decompress after being taken to a new home, three weeks to get settled to your routine and three months to really feel that they now have a home and to bond to you.  We prefer a secure fenced in yard for these dogs and when walking to use a harness rather than a collar to keep them safe.  The one we recommend is the BOLUX dog harness available on Amazon.  Most will take the small or medium size fits most.