You’ll want to have your office hours in the voicemail so that cleaning customers know when they can connect with you. You don’t have to always be available during all of those times, it’s just the possibility you’ll actually pick up your phone or will be able to give them a call back during those hours. Adding in office hours makes your business sound much more professional. It’s the sign of a more established, well-run company to have business or office hours.
There is no definitive answer here, but you should include one of the two at the beginning of your message based on what makes the most sense.

The phone you use to record your greeting – and your surrounding – can turn your carefully scripted greeting into an unprofessional mess. Background noise is terribly distracting, so choose a quiet room or parked car to make your call. Landlines, or a “wi-fi enabled” cellphone call, can provide much better connection quality than a standard cellphone. If you must use a cell phone, be sure to use a high-quality headset for the best clarity.
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