Best Solutions for Stable Internet for Event Live Streaming (portable hotspot? personal router? other?)

Hey, everyone! My apologies if this question has been addressed, but I couldn't find any threads that really answered my query.

Essentially, I work as a videographer, and I occasionally livestream different niche sporting events. They are always in different venues (albeit almost always indoors) - event halls, gyms, schools, etc.

Obviously, the stability of the internet varies quite tremendously at each location. Connecting directly to ethernet is not always possible, so I'm hoping to find some options that I can bring with me to these venues to ensure I have a connection that will provide stable upload rates so that I can operate relatively stress free.

Are portable hotspots the best option? I assume most of these come with additional fees for monthly data use? What about bringing my own router and being the only device to connect to it? What other options am I missing?

If there are some specific products you would recommend, that would be wonderful. Thanks, everyone.