But 100 yards is well inside the maximum length of an Ethernet cable so one long cable to a WAP or a "ROUTER AS A WAP" will fix this for cheap. A better solution is an optical run since it's immune to lighting strikes.

Now that you know consumer gear is a dead end, you can research commercial solutions.
https://www.amazon.com/TP-Link-CPE210-300Mbps-dual-polarized-directional/dp/B00P4JKQGK/ref=as_li_ss_tl?ie=UTF8&qid=1524111688&sr=8-5&keywords=tp+link+long+range+outdoor&linkCode=sl1&tag=m0158-20&linkId=3012bc16328f2e17fbc89a70725f5102

You'll have to have a good network person in your employ to finish this off.