This, in itself, wouldn't be so bad, but the phone supplier we went with flatly refused to help us out after the sale. We ended up having to contact another vendor for the information we needed to make our new phones function properly.

First, and let me stress this; always contact the vendor prior to the purchase. Not only do you want to know who you are dealing with, you need to know if it is someone who can and will answer your questions and who will stand behind the products they sell.

Second, always go with a vendor who has more than one option for phone systems. We found out after we had already purchased our new phones and equipment that there were phones on the market which would have served our specific needs better and would have cost less than the phones we went with.

Third, always think about compatibility. We thought that because we had purchased the same brand of phone, that we could simply switch out the new phones for the old ones and that our line equipment would never notice. We did ask the supplier before the purchase if there would be compatibility issues and were told, "it should be fine". That should have set off a red flag, but one likes to assume that someone selling phones might know a thing or two about them. See rule number one.

Finally, do a healthy amount of comparison shopping. We went with the first supplier because he was the cheapest of three that we had looked at. Three was nowhere near enough. We found out after it was too late that the vendor we contacted for help had the same phones for cheaper (although he would have been kind enough to steer us toward what we really needed) and offered far superior customer service.

In short, purchasing a new office phone system, whether you have five lines or five hundred, is a big investment. Follow the step that we didn't, and you'll save a lot of time, money and effort. You'll be glad you did.