A good home office or small business phone system will typically range in price from as little as a few hundred dollars for a small intercom system to several thousand dollars for a more versatile system designed to serve an office with a few dozen employees.

As residential homes get larger, more phone lines are required for computers, fax lines and, of course, children, it's not uncommon for many homes to have four lines, especially in homes ranging between 3-5,000 square feet. Just as no car suits every driver's taste no single phone system is right for every home or business.

Phone systems: Expandibility is an important issue. Some vendors will tell you to throw out the old system and replace with a newer model when you grow beyond a certain size. This can be both disruptive and expensive. While no phone system will cover all possible business bases, the system should scale well from a few phone lines to a few dozen lines and stations wiithout requiring replacing the basic system.

Any phone system should work with either vendor supplied telephones, or with ordinary analog phones. If it doesn't work, don't select it. The same goes for for voice mail compatibility.

Automation: You can often automate your phone system without tipping the customer off that a computer (or "brain") is involved. (An in-house computer coordinates activity on phone systems which are a step above an intercom system.) A classic example is a Caller ID lookup. As a call rings in, the computer captures the phone number , sees it as an existing customer, and transfers the call to an employee who has worked with the caller.

Intercoms: Intercom systems are great for small businesses where you have fewer than 10 employees, most of whom are in the same room. The main advantage is price. They are inexpensive, use existing wiriing, and require no knowledge of computers to use. Their main disadvantage is lack of flexibility. It's often difficult or impossible to expand intercom systems to include automated voice mail, to go beyond a certain number of phone stations (usually 8, 10 or 16) or to stemline the handling of some kinds of phone calls (high priority) without human intervention.

Think about the future: When adding new phone lines, always think about future use. You might not want a fax, internet or phone line in every room of your home now, but perhaps you might in the future. It's a better idea to add phone lines where you might want them in the future; every time a service professional comes to your home, it's an added cost.

Access: Wall access is an important factor in the final cost. With better access, your service professional can do the job easier and more quickly than if access is limited or if walls need to be kept intact.

-- Tips courtesy of HomeAdvisor.com