I take it your friend does not have broadband at the moment. If so, the value package requires a £25 activation charge which is only waived if you sign up for a 12 month contract and also move the phone to PlusNet. So that info was wrong.
As for the pricing, that is probably correct. If you go to the plusnet home page then click on the more info for value it says the following:
"Around 80% of homes can get Plusnet Value for £6.49 a month, making it the UK's cheapest stand alone broadband. If your home's not in that 80%, it's £6.49 a month for three months, then £12.99 a month after that.".
Now what you pay depends on whether the phone is on a market 2 or market 3 exchange BUT, in both cases the initial monthly fee for 3 months is £6.49 so the original conversation was actually correct and the agent concerned should have indicated if you were on a market 2 exchange then the cost would rise to £12.99/mo. Maybe that bit of the conversation has been forgotten or was not understood by your friend. It's possible the second call correctly stated the final sum payable would be £12.99 if the phone is on a market 2 exchange.
The costs are clearly stated on the website but it depends on whether the phone line is on a market 2 or 3 exchange. To find out, on the home page, click on the availability icon under value, put in the phone number and it will tell you what the costs will be.
