Do I need an ISDN line?

I’m totally new to asterisk, but I would like to build a system for my small company.
BT are telling me I need 6000 pounds worth of equipment but I thought I could just get away with an ISDN line and asterisk. Am I correct?
All we need is a line that allows 2 calls to come in and go out and then we connect that to our asterisk box, don’t we?
Also can anyone recommend a pbx card for small businesses.

Many thanks

How about investigating using a proper VoIP supplier to provide you with two PSTN dial in numbers, then all you need is your Asterisk server and an internet connection. You could start with two lines and easily add more if you require. I don’t know how much ISDN costs but I presume you’ll have an internet connection anyway so this might save you money.
If you are worried about making phone calls if your internet connection fails, you could get a PSTN card for your Asterisk server as a fall-back. Pick the right VoIP supplier and if your internet connection is down, they will forward the calls automatically to your ‘backup’ land line.

That’s how I’d do it, anyway!

Thanks for the reply,
I see what you are saying about routing the calls with Voip but I am still confused about the PSTN lines, I thought you if I had two PSTN lines that would be two separte phone numbers. We want one phone number and be able to recieve two phone calls at the same time.

b410p misdn bri card, or 2 1xPort isdn card’s (not used them so not sure about quality)

With b410p you install misdn(kernel-headers before on debian) configure run “misdn-init configure” edit misdn.conf and feel happy.