Yes, not only will you save money using an auto attendant, it will generate revenue for your business. Instead of sending callers to your voicemail when they dial your cell phone, you can handle their call, especially if they want to reach "sales." When someone wants to do business, they don't bother explaining it in a voice mailbox. You can also configure your auto attendant to automatically route calls to a live operator or answering service. When you're back in the office, you can answer calls from your business phone number.