I looked at a few, but the place I rent is about an acre (1.06 or so), and the building on the acre covers like none of it (like 960sqft lol) Toss in the drainage ditches by road and being in a constant flooding warning recently I figure I need to wait. I saw a cool one that said it MAYBE could do the hills if I mowed them short first, then just had it auto keep thrm short all the time. But that thing was about $3000 by the time I set up the solar charging station and what not. Ended up just getting a cheap lawnmower cause I didn't have the money to chance spending all of that and still not being able to get the lawn mowed. Also I figure I'd not realize it rained last night and the robot would go about it's schedule straight into the water in the drainage ditch or something.