I would start with .... NOT moving in with her. I smell a spoiled rotten brat that automatically assumes people are going to give her what she wants. It's the "entitlement" mentality and it seems to be running rampant. Don't go there.
IF by some odd reason or for whatever reason you can't get out of this entanglement ... then ...
Originally Posted by Speed Racer
Don't lie, whimper, or fight with her. Just tell her flat out, 'This is MY trailer, and you are NOT to use it unless I give you permission. ' Then get a hitch lock for it so she can't go behind your back.
^^ make that your motto!!