I'm not sure what you mean by "little money" but for less than $100 per location, you could have a 100+ Mbps link using Ubiquiti NanoStations. You can use Wi-F

I'm not sure what you mean by "little money" but for less than $100 per location, you could have a 100+ Mbps link using Ubiquiti NanoStations. You can use Wi-Fi or their proprietary protocol and the radios are available on 2.4, 3.65, and 5 GHz. These little things will cover your 500m link with ease but might very well be extreme overkill if all you really want is <= 1 Kbps throughput.