NewbiwVoIP setup help

[Clueless_dude]

Hi,

Firstly can I apologise for the simpleness of this post. As my name states I am Clueless!!! - I have looked across the site but could not get a definite answer and didn't know if I was talking / thinking a load of rubbish!

I have been looking into setting up a VoIP system for my dads new office.

We have a small office, where two maybe three people will work. We have 1 BT line coming into the office, and we also have a broadband connection.
Basically we needed a cheap way of having two phone lines. We had a few people come to "advise" us, but unfortunately they where not able to go into much detail of products and services and just seemed to want to sell us things!! I got the impression they didn't really know what they where talking about!! - So as I'm not happy to pay for services we don't need, thats why I'm here really!!

OK so the idea is we want one phone in the office, and then a dedicated line for a fax machine. It would be good if two calls could be made ie one from the "main" phone line, and one from the "fax" line, but thats not that critical. - The main requirement at the moment is, we don't want to lose phone calls while the fax machine was busy.

First question, from what I've read the above requirement shouldn't be a big problem, am I correct?!

One of the suppliers we got in did seem to talk a bit of sense but came back with a ridiculous quote. The supplier suggested some hardware which I have heard of and used at a previous company. They recommended a ZyXel P-2602HWL, which we could use for VoIP and also as a wireless router (I managed to pick one of these up super cheap off ebay - which was a bonus!!).

Now second question. - The supplier said we needed two SIP accounts. I'm not really sure why ?! - Could anyone offer some advise? - Looking at VoIP providers they don't really seem to offer separate SIP accounts, the impression I get is when you take up a VoIP service from a supplier they just give you one SIP account and thats it.

Thanks to all you lovely people in advance for reading this, and super super thanks for anyone to offer a reply!!!

Clueless