Take a look at ArubaInstantOn APs. They are about $80 each. I have 3 of them in my RV. The mesh master plugs in to my Pepwave Surf SOHO MK3, and then creates a mesh network with the other two devices. I have turned the local wifi off on my SOHO MK3 but use it for WiFi-as-WAN connection to the RV resort wifi. The Aruba devices are very simply to manage, and can be managed from both a web interface as well as a mobile app.