two year old chihuahua

Question
how can I get my male chihuahua to stop weeing all over my house? He even wees on his dinner and if anything is left lying around he wees on it. I also have a female mungral she is old. Oscar my chihuahua is very frisky towards her and she doesnt like it.  I have bought a bitch spray to try and keep her off her sent but nothing seems to be working. Also Oscar barks at everybody who enters the house even if he is familiar with them.  Im at a loss and would really appreciate some advice on how to train him

Answer
I assume your male Chi is not neutered and it appears that your bitch is not spayed.  However, even if she is spayed, the intact male knows she's female.  He seems to be marking everything in sight in order to establish his right (as male alpha) to the older female.  He must be neutered.  This testosterone related behavior will slowly extinguish, although some marking behaviors will remain because he is being neutered past 18 months of age.  After he is neutered and his surgical area has completely healed (several weeks), buy a belly band.  This is a device which prevents the dog from urinating inappropriately and they are available online.  Following several weeks of being self regulated by this device, he should stop attempting to mark indoors.  You can safely remove it and watch him closely; be certain to reward his appropriate urination outdoors during this transition period (although he's not exhibiting house training problems by marking, it can generalize.)