I currently have 4 telephone lines, and no switchboard, and one ip phone that is connected to a dialler in India - I use this for verifying and hot-transferring mortgage and secured loan leads. This portion of my business is growing, and I need to expand to four agents, 2 would be remote and 2 in the office.
I would like to setup my own predictive dialler, and to be able to use the outbound lines in the process, so that any line can be used for some outbound calls, and for the hot-key transfer (teleconferencing really), and so that if an inbound call needs to be transfered to a remote agent, I can do this as well.
Im ambivalent whether to host the dialler (opensource of course) on my premises, or on a hosted server.

Is this possible? If not, what do I need to setup this just on IP phones.
And what cost?

posts or pm's are welcome
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It's not obvious from what you've posted why you want to mix POTS and VoIP. It would be far easier to do what you want just using VoIP.

Using just VoIP you just need 4 or 5 extensions, some phones and broadband connections wherever you have an operator.

Can't offer any advice on your dialler but I'm sure there's stacks to choose from.
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If you want VOIP/POTS integration then the PBX will need to be on your premises, as things stand ATM. I think voipfone are working on integrating POTS lines into their Virtual PBX, but I don't that's in place yet. cjd will doubtless correct me if I'm wrong.

You could consider one of these:

http://www.voipon.co.uk/atcom-ip04-4port-asterisk-ip-pbx-p-747.html

(and there are other places to buy them), or a local Asterisk/FreePBX type server.

From a business perspective you might well get better VFM from a hosted solution, but is your internet up to the number of simultaneous calls?
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I think voipfone are working on integrating POTS lines into their Virtual PBX, but I don't that's in place yet. cjd will doubtless correct me if I'm wrong.

We do a CPS (POTS) service that has some VoIP features like call tarnsfer, music on hold, call recording, without needing any new equipment or a broadband connection and we will be integrating a more complex inbound product in the next month or so.

https://www.voipfone.co.uk/Voipfone_For_Your_BT_Line.php
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Have a look at Trixbox (www.trixbox.org). This can provide everything that you need and more. With this you call also use http://www.venturevoip.com/st.php as an excellent industry strength dialer platform. Trixbox is based on the Asterisk IPPBX system which can support VoIP and PSTN as well as ISDN.
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