my ?chihuhua ?

Question
i am a college student and i am to be married in july.  my soon to be husband and i are moving into a house intown(small but large to me).  my family had three dogs until recently.  we had to put our almost 13 yr old rat terrier to sleep from old age (he was also ran over at 18months old and had a bad leg).  sense he (bandit) has been gone, i have seen a change in the other 2 dogs.  my dog, gordy, is half rat terrier and half miniture shelty.  he has always been timmid and now has grown more of a backbone.  the other dog, buddy, we arent sure what he is because he was a stray.  we think he is a chihuhua though.  when i move into this house i am taking the 2 dogs with me.  i actually have a few questions about this.
1)when bandit got older he started peeing on the walls, therefore the other 2 dogs started to do that too.  how do i break them of this habit before i take them into the new house?  
2)how long do chihuhuas live? and do they get mean in their old age?
3)sense bandit has been gone buddy, the chihuhua, has started to growl at walls and just about everything.  he picks fights with gordy who is bigger then him.  he will curl up UNDER a blanket and if gordy walks by then he will growl at him.  when i am at home, my sister and i share a room and the beds are lofted.  when i am there i was putting both dogs in bed.  gordy will sleep with me through the night most nights.  buddy will sit on the other bed (the beds are at an L)and growl at gordy.  at one point he would look at mean and if kasey (my sister) would look at him he would just look cute.  how do i break buddy of being "bossy" to gordy?  and will he change once gordy is gone(he is about 8)?
4)when gordy is gone and it is just buddy would it help to get a new small pet?  he does well around other animals but he just is really "bossy" with gordy around the house.  
5)(sorry i just keep thinking of more)buddy will sit by you on the couch and claw your hand so you will pet him.  how do you get him to stop?
thank you so much for you time and sorry for the length and number of questions


Answer
Hi Katie!

Please don't apologize for asking questions, that is what we are here for.   First, I have to tell you that Buddy is displaying typical chihuahua behavior and probably will not change.  I have a 10 yr old male chihuahua who does the exact same things that your Buddy does.  He also will be under a blanket and growl at the other dogs and if they dare to jump up near him, he bites their head off!  Chihuahuas think they are Dobermans, and you will not be able to change his behaviour.  I have six dogs, three of which are much bigger than my male chihuahua, but he is definetly the alpha dog, the leader of the pack!  When he growls, they listen!  lol
Chihuahuas can live to be up to 15 years old and older if taken care of.   
About the peeing in the house.  You need to have both of your dogs neutered.  It may be too late, they may still "mark" their territory, which is what they are doing by peeing on the walls.  Always spay or neuter your pets... they are much better pets when you do, and they are happier too.  You may want to consider putting them up when you're gone, not let them have the run of your new place until you see how they will react.  Just remember,  a new place means they will want to "mark" their territory even more, so I would strongly urge you to have them both neutered.
As far as the clawing goes.....he does that for attention and that  is his way of tellng you what he wants.  You might be able to break him of this by firmly saying NO when he does it.  
A small dog would be a good companion, later,  for Buddy... but don't expect him to change.  He will still be "the boss" but it might make him more playful once he gets used to the idea of a puppy.   

Good luck and God Bless!
Becky