Planning on adding a chat widget / chat bot

We are planning on adding a chat widget / chat bot to support customers, linking it to our help centre, we might use a tool called intercom or crispy, we want to make sure its right for us. They both have start up offers, however our concern is if we scale up in the slightest we have to pay alot for intercom. Also we would also think of forking and open source chat widget and product tour to make it more secure and private. The less third party softwares we use the better.