If we are at work, ours is in her kennel (she is six). When I am ready to leave for work, she just goes in.
I come home at lunch to let her out, or I have my daughter come over. She is also in there if we are gone for more than a couple hours. We have done that all of her life, but we have started letting her have the run of the house more in the last couple years if we are only gone 2 hours or so. She will still leave us a surprise
if she has to go and we are not there. When we are home, she has had the run of the house since she was about one. In the last year, we have noticed that she sleeps more, and we can trust her more, but it has really taken a long time.