I only interview after hours. I have done a few where parents would insist coming during daycare hours and ALL of them were a nightmare. The children would act up because I was focused on the conversation with the interview or I would lose my train of thought about my program because I would have to tend to the children and then not remember what I had or hadn't already mentioned about my program.
No one has ever signed who came during daycare hours. Now my firm rule is after hours ONLY.
Imagine doing a job interview for any other job while you are watching 4-5 children. Not a good scenario.
I like to do interviews somewhere between 5:30 or 6 p.m and expect them to last about 45 minutes to an hour. It gives me about 20 minutes to tidy up the house and have a few deep breaths.
I have recently done a couple of weekend interviews and I actually liked that too. It gave me the morning to tidy up and then be very calm for the interview.