Your use of the phone will change drastically if you work from home. We asked Tim Farrar of the Cambridge-based telecoms consultancy Analysys for some advice.

Should you get a second phone line?

It is not worthwhile unless you want to separate your business and residential calls, or if you are likely to make long data (eg Internet) calls.

Won't it be difficult for people to get through?

Business and residential phone patterns are so different that calls are unlikely to overlap.

If I don't go for two lines, should I use Call Waiting?

That is an option, but be warned that people don't like voice-mail systems.

If I do want a second line where should you get it from?

There are plenty of discounted lines around. Some of the cable operators are willing to install a phone line free of charge. Some charge higher rentals and lower calls, some the other way round. Check them out carefully.

Is it worth getting two lines from a cable company?

It could be. Some cable companies and the new telephone company Ionica, which is only operating in East Anglia, will do rental on the second line lower than the first so you could win out that way. And with number portability coming in, this becomes a more attractive prospect.

What is number portability?

The ability to keep your own number when you change operators. Check with your local cable operator to see when you will be able to keep your number. Most operators will have it up and running probably this year.

If I stay with BT, is it worth changing from the residential to the business tariff?

You get a better repair service and better discounts on business lines. But you have to be spending quite a bit before you make a saving. In July, a residential line rental goes up to pounds 25.69 a quarter and a business line to pounds 41.13. BT reckons you need to spend pounds 200 a quarter for it to be worth changing, but we think that figure is too low. With discount schemes changing every month, however, it is difficult to tell which is best.

What if I make a lot of international calls?

Resellers such as WorldCom, ACC Long Distance and Dial International, who advertise in magazines and newspapers, can be extremely good value. These companies bulk-buy capacity on international phone systems and then sell calls to individual users. The call quality is not quite as good as BT and Mercury, but most people won't notice the difference. They would put with slightly worse sound for a significant discount.