40GB/mo is stingy for the current Internet environment.
Depending on the
customer and your own tolerance for technology, enterprise grade networking can incorporate multiple Internet feeds and you can throttle bandwidth to each of the home's "clients". An option might be the
Access Networks approach (they'll work through A/V installers). The multiple feeds could be a combination of multiple Wildblue accounts and 4G. You'd need to cost things out over a multi-year, total cash outlay basis (including hardware purchase, monthly traffic and equipment fees, and your management fees).
If you need to improve 4G coverage on the property, amplifiers are available.
"Management" for multiple feeds could be as simple as mechanically swapping cables throughout the month as each feed reaches its threshold. I'm not suggesting that this is a viable approach in all situations, but the technique is available (and relatively low cost) for motivated
customers.
With respect to the 4G account(s), keep in mind that the usage threshold will include both on and offsite use. If everyone is watching movies on the road, there may not be any bandwidth left over for home use. I know that 4G carriers are pushing "unlimited", but there is "fine print". Make sure that the fine print makes sense in this environment.
Nasty fact of life: 4G and Satellite
have limited capacity compared to cable and fiber. Providers must manage (limit) traffic, somehow, or the system will collapse under the ever expanding load. Cost per GB and/or throttling are management techniques.