The advice to me was to set up a separate line for business calls and broadband*. I didn't take that advice as I was still recovering from my last encounter with BT. Frankly I didn't trust them to set up a second line without screwing up the one I had.
*The mothership will typically beam down black-suited operatives to achieve this goal. As Jake says, generally your employers should take full responsibility. Our typical homeworker set up has BT installing a second line purely for business calls and broadband (which isn't supposed to be used for other than incidental personal use, but can't realistically be policed, I don't know anyone with a second broadband connection on their personal line). I'm not typical, since I was acquired as part of another business.
So, the best option for me, to avoid tax liability issues was the mothership to take over my current set up and pay for all broadband and calls. Attempts to itemise personal usage turn it into a taxable benefit. Better to assume that it's a business asset, that like my business mobile, is used occasionally for personal use. It's arguable - the view was that it was the primary and majority use for both the phone and broadband. Certainly for phone bills, the cost of the line itself and business calls means the bill splits about 95:5 business to personal, which I think is fairly 'incidental'. Harder to quantify with the broadband, and I expect it would fall over on this if probed. At some point I may still have to be ready to let BT devils into my premises. Horror followed by endless darkness.
As a designated homeworker, the mothership provide for all equipment. Laptops, phones, monitors, docking stations, printers, ADSL router/modem, desk, chair, and anything that can be reasonably be construed as essential for the purposes of continuing business from home.
They do not contribute to heating and lighting. Partly because of the liability issues above and partly because they're mean.
