I made this remote controlled lawnmower using the Sabertooth 2×25. The motors came used from and electric wheelchair, and the mower itself was graciously donated by my dad. For me the build cost about $900.
The cheapest radio transmitter/receiver set that I could find was from robotshot.com. The link is here: http://www.robotshop.com/gws-radio-control-system.html
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