@EvenSteven-1_ 

It may not help as the interference will still be there as all routers must operate within a specific band.

First thing I would try is change the WIFI channel and band width. You want to use a norrow band width to reduce interference. A different channel may move you away from the interference. 

Try moving your router to see how it affects things. Higher is better, move it left and right as much as you can. Turn it different directions. If the antennas are removeable, be sure they are snug. 

Turn off smart connect and use different SSIDs for each band. Leave hide SSID off. 

Try blocking the interference item with tin foil, sheet metal, ...

A MESH may help as would an AP or extender but a router should be able to cover 1500 feet. A onemesh device can be added to that router. I would try an inexpensive extender first. An extender, AP or MESH should be placed in an area of a stong signal for it to work best (example: half way to trouble area not in the trouble area).