I have understood that you want a chat client, so is it like a Web App or intranet application? How about if we use some 3rd party chat module & customize it as per your requirements?
I think one to one technical meeting is important to make sure that we are both on the same page in terms of requirement understanding, after that we can finalize everything to kick started.
So, please click on the chat button to schedule a meeting time, after that I can revise our bid.
Look forward to hearing from you.
Regards,
YK
LEADconcept