Keeping a couple of horses on 1/2 acre requires good management but it can be done, especially in So Cal where it's really dry most of the time. Look for Horse zoning, and check for CCR's, codes covenants & restrictions, that would limit your ability to keep your horses at home. When I lived in So Cal, it was SOOOO much easier to muck out, the poo dries up and weighs NOTHING, never stays wet & heavy. I had my riding area (NOT an official arena but it was fenced) and I put the manure in there and disc'd it into the dirt every week or so. My arena was 150 X 300 so it was a good sized area. Off the side of the arena I had individual pipe corrals 24 X 24 with a corner shelter to protect from wind/rain/too much sun. I graded the corral areas so that they sloped a bit and the water ran off and mud was rarely a problem. Of course, when you get those So. Cal. Downpours that occasionally last for 3 or 4 days, anywhere becomes a soggy mess. Because of the dryness, I never smelled the manure or urine in the house, nor did I have a big fly problem because of breaking up the manure and discing it into the dirt in the arena. I also had a swimming pool, never had a complaint about the smell from guests over for swimming and a BBQ. I was in a horsey area so never had a complaint from the neighbors about the horses, nor did they find any extra flies. I also hung those big Rescue fly traps around the stalling areas, they trapped a lot of the flies and fly predators did a pretty good job with the rest.