mtnmama
Keep in mind that you're free to use a 3rd party router with HughesNet. Some 3rd party routers have the ability to set daily limits, or even limits by device. You can go on the forums of the various router manufacturers (if they have a forum), or even their social media pages, to see if one of their routers, with their stock firmware, would fit your needs of a daily data limit.
There are also 3rd party versions of firmware available that can give many more control and settings options for a particular router. The two main ones are Asuswrt-Merlin for ASUS routers and DD-WRT for many others. This is a little more complicated and risky, as it can be quite tricky to flash a router with non manufacturer firmware, and doing so incorrectly can actually "brick" a router (ruin it), but it can be well worth it. If you're not used to working with computer/network related tech, the option mentioned in the first paragraph, as in a router that can already fit your needs without needing to change the firmware, would probably be the better one.
The two firmware versions mentioned and linked to above have forums listed on their sites in which you can ask questions, as in what router using that particular firmware might fit your needs.
Hope this helps. :)