How do I go about getting an extra person added to our housing contract AND listed in our official Military documents with DEERS and Tricare?

I am having to take in a extra family member for a few months and maybe permanantly. But I want to have everything in writing so no trouble will come of this. Any help is very appreciated!

Thanks in advance 

are they an adult or a child? We tried getting my husbands father on our deers so we could take care of him since his health is so bad but they denied us because he made too much money (he got 800 a month). It was a bit of paperwork, and I dont think they will only do it for a few months. If it is a child you have to have custody of them. 

we put my father as a dependent its a lot of paper work ...he makes 900 a month but we had to show we provided more then 50 % of his care...if its a kid im sure its different... 

He's an adult, my brother actually. He's 22 and has no income 

We tried getting our niece on our deers because her mother threw her out of the house and was told no because she was 18 (an adult ) and she had no disability that affected her being able to take care of herself. 

Hopefully this helps. to enroll a family member in deers under you, you must go to the ID cards section to get the packet they have and fill it out completely. You then give it back to them and they send it up to HRC. It is HRC that says yes or no. For housing you just need to go to Piercne to get exemption to policy and have your unit sign off on it. but housing will not do it unless they are a dependent of yours