Go to the "Demarcation point", which is where the phone wire from the outside pole comes into your home. If you see a separate pair of wires attached there for each phone in your home, the chances are you already have "Home run" wiring. If you have five phones, but less than five pairs of wire at the demarcation point, then you're going to have to do some work. This is not a 100% perfect test, but it's a good place to start.
What wiring? Do you mean daisy-chained wiring, or a separate line for each phone?
You'll have to answer the question of "what PBX features do you find essential?" before you can make an informed purchase. First, ask yourself "What am I trying to accomplish?", and make a list of the things you want the machine to do for you.
For example, do you have someone at home with limited mobility? Are some household members working off-hour shifts? Do you have a need to audit either cost or time on calls? Do you require the ability to shunt all calls to voice mail without audible ringing? Do you want wake-up or other notification features?
Once you have a better picture of the system that you want, _then_ you can ask "Which one is best?".
Start with this list:
- Can use Category three wiring, the kind in most homes
- Maintenance available from local firm
- Major manufacturer
- Paging, music-on-hold, other features
- Reasonable cost
- Ease of use and ease of programming
- Good used market (check Ebay, other sites)
- Compatible with existing instruments
When you've decided what features are "Must have" and which are "nice, but not essential", you'll be ready to look at the available systems.
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