I find your question a bit odd given that you referenced a partition action in the subject header of your post.
A question for you: If your grandmother only died six months ago, has title to the property actually been transferred to the two of you, or is probate still pending? If probate is still pending, there's probably an easier and less costly way to deal with this than a partition action.
There's a person who used to frequent a couple legal message boards who would recommend to you that you start throwing parties at the residence for local biker gangs and such. After all, it's your home too. Not that I'm recommending that.