Get wifi antennas. My buddy was beaming internet to his parents place 5km away with 300mbps speed. As long as there is straight shot sight line you can beam fast wifi across your property easily.

Speaking as a simple datacom tech, are you living in your own house or an apartment? What’s the cabling going into your place? I could sign up for gigabit speed at home but I know I’ll never get more than 150mbps with the infrastructure I have. Maybe you can blame a 500mbps loss on a router but that wouldn’t be my first guess.