First and foremost, I agree with each and every person here who says that outside is no place for a pig!
Living in Ontario, I don't have first hand experiance with LA or its climate, but I would imagine it to be dangerously hot outside for a guinea pig and not at all suitable.
That being said, this forum says "Outdoor Environments Not recommended, but if you must, do it right!"
From what I understand, you do not own a guinea pig yet, meaning, you "don't have to" house one outside, you have the choice of not adopting one or two at this point!
That may seem really harsh, and I am sure you really want one, but it would be very expensive to get a proper outdoor setup, and chances are, your pig would die very prematurely, not to mention live a hot / uncomfortable lonely life. I am sure that is not what you where planning at all!
Good luck with getting a better living arrangement, as I am sure you have lots of love in your heart to love a pig, and there are certainly many pigs needing love in your area!