I am sure Texas isn't like this, but isn't there some states that if you are gone for that long squatters can move into your residence legally and stay?
Just kidding, but I'm not so sure someone didn't tell me that can happen in California.
I know you mentioned "renting is out of the question", but I will make a suggestion anyway. Visit you local Sheriff's department or police department and see if they have any new officers that are looking for some place to live. New LEO's don't make much money for the job they have to do. If you got the right young person in there your house would be extremely secure, well maintained, utilities paid, and you would get the satisfaction of helping someone out that spends their days helping everyone else out.