A home business answering machine offers a few distinct advantages over a voice mail system. While you may have to pay a monthly fee for a voicemail service, an answering machine simply incurs a one-time purchase fee. In the 1980s and 1990s, the devices did usually require a mini-cassette. However, modern systems are usually digital and thus will not require the upkeep and possible purchase prices associated with mini-cassettes.
Another key advantage is the ability to screen calls. With a voice mail, you cannot hear the message as it is being left by the caller. An answering machine enables you to hear the message as the caller speaks (unless you are not near the device) and you could therefore pick up the call if needed.
If you purchase this for your home office, the price is often tax-deductible as a home business expense. However, check with your accountant or bookkeeper if necessary to ensure this applies to your specific company structure.