The first heavy cost would be the cameras and operators. If you will rent a production-quality camera, plus the operator, it can easily cost you about $500 to $2500 but it all depends on several other factors. You can live stream using your phone camera, but that would mean the quality is sacrificed.
What would be a good alternative is using a DLSR camera that’s about as simple as your phone camera but offers considerably good quality live stream. Compared to production-quality camera and phone camera, it is the best option for you when you are short on budget.