Family feud over living will My grandfather’s living will declares my mother…

Family feud over living will
My grandfather’s living will declares my mother and my aunt joint owners in all of his property (car and house – with everything in it). Here where my questions (1) The time spent by my mother and I maintaining his home (since 1987), cooking to his diet guidelines, cleaning, electrical work, etc – shouldn’t that be taken into consideration as our investment into this home? (2) Not everything in this house is his, all 3 of us live here, my mother and I do not have receipts for stuff we bought years ago – why do we need to prove that it belongs to us now? (3) All of the household bills are in my mothers name and have been since 1987. As far as most companies are concerned this house belongs to my mother. (4) Lastly I have been paying the bills that are in his name since January of this year, can I expect to see any of that money back now that he has passed? The primary reason for my concern is that my aunt wants to list the house for sale, yet my mother and I still live here. I have no problem with the plan of paying my aunt a third of the homes current value after it is inspected by a pro. I just don’t agree with paying her half the homes value along with her keeping his car and taking most of his stuff.
So what can we do?