Hubspot has a good live chat plugin that you can incorporate into your WordPress website, and it is Free. It also connects totheir CRM system and automatically saves the data and shows you how many time the user visits your site and give you more stats, which is good.
It also provides a WordPress plugin that you can download and install through your WordPress Plugins page and set it up in no time.
You can start with their free package and try it out.
Hope this helps
PS: If you have any questions or comments, please leave a comment below