Yes, we provide 24/7 live chat support.

Depending on that actual issue, quite a few issues can be handled with live chat as its normally a simple setting that is off or needs changed. However more complex issues will have to agree are better suited for helpdesk as some things do take more time to diagnose.

Live chat for sales and billing are a must I believe, its like going into a store and not being able to find anybody around to answer your question same thing applies for online.

Depending on your market, will determine if you offer it and what hours. Might not be suitable for budget hosts as the costs to offer it might exceed profit margins.