I used a few web page size tools and I'm picking the number of 0.25 megabytes for web pages today.
Hit Yahoo 4 times and that's a megabyte. In a month it would be too easy to break through 1GB and we didn't even watch a video on YouTube.
Videos on say 1080p exceed 1GB per hour.
My cheapest cell plan is Unreal and I use their GSM AT&T towers. https://www.androidguys.com/featured/opinion/unreal-mobile-review-cheap-cell-phone-plan/ agrees with my findings. It slows down as I hit the stops.
I've been doing a lot of searching over the past few weeks about wifi hotspots. I've never had one; I've never had the need for one. The reason I'm searching about them is they were mentioned by a friend of mine for my mother who lives in the boonies and the only thing available to her is HughesNet satellite Internet. She currently has it and it's quite expensive, restrictive, and very slow. The only cell phone provider that gets a signal where she is would be Verizon.
So I was thinking, what about a Verizon hotspot? I've read conflicting reports on this. She does not use much data at all. In fact, I'd be surprised if she would use 1GB. She just does normal browsing. She is not used to being able to steam, etc as you really can't with satellite internet anyway. The satellite Internet bill is up to $59.99 a month for slow service; painfully slow. Given Verizon gets a good signal there, would a wifi hotspot be an alternative? She does not own a cell phone but was thinking if she did, it would obviously have to be Verizon..but for right now, she's still attached to her landline.