If you are live-switching in between various camera feeds, slides and other sources in your event that could significantly raise your cost. The streaming hardware is also expensive and your bandwidth needs also vary. With all these, there is considerable change in your expenses for the live streaming.
The best thing that you can do about it is to catch up on your technical knowledge. This way, you can find of an effective alternative way that is not so expensive but doesn’t sacrifice so much of the quality of your live streaming production.