In 2014 my sister and I hired a lawyer to do my moms living trust and will. Here we are in 2018 and my mom has dementia. She lives with her sister, a retired nurse who is well off financially. My sister sold my mothers property and the money was supposed to go to her trust. In my mom's will everything was supposed to be split evenly between us, except for her car she gave to me. My mom can't drive so I asked if I could use it and my sister informed me that she bought it, is this legal. I'm sure her and her family has spent all of her money and as far as everything in the house I didn't receive anything she cleaned it out. Do I have any rights here?
If you are considering any action, no law enforcement people are going to act on that basis. You need facts and documentation.
I think there are too many assumptions and conclusions. The best way is discuss these issues frankly with your sister, and learn about what she and her family have sacrificed to care for your mother. Unless you're walking in their shoes, it's difficult to judge them fairly.
You might want to read some other posts here about the sacrifices caregivers make, even if they are well off. That doesn't compensate them for the emotional challenge of caring for an older parent.
The Will is not effective until your mother dies, so there's no basis to conclude that disposition has been made unfairly.
What proof do you have that the house proceeds weren't in fact placed in a trust bank account?
This is not a criticism; it's a suggestion from what I suspect may be some suppositions that need explanation. Mend fences with your sister, or offer to visit her for a few weeks to take over the caregiving and give her a break.
I have an impression that your family's communications have suffered, perhaps, from what I'm coming to think of as "sporadicism." You and your sister teamed up to arrange the trust in 2014 - so then, presumably, all was plain sailing between you. Since then, there's been the car issue (why did your mother have a car at all if she doesn't drive? - was it perhaps initially your father's car? - but never mind, it doesn't matter) and the house sale and the furniture clearance: dealing with all of these things involves actual footslog and elbow grease. Were you perhaps not on the scene when they were being dealt with as part of the major project of relocating your mother?
To play devil's advocate for a moment - you took an interest in the car when you wanted to use it; but what about when a place needed to be found for it? You're feeling excluded and hurt that you weren't given an opportunity to select keepsakes from your mother's home; but were you there when it came to carting away the trash and cleaning the skirting boards?
If you have good evidence that your sister has been misusing your mother's money, then yes you must report it - that would be financial abuse of your mother. But if this is more a matter of your natural wish to know a) what has happened and b) where you stand, then I hope communications haven't broken down so far with your sister that you can't just have the conversation with her.
Since your mother is still alive, the will has nothing to do with the present situation, although a loving sister would have realized it was meant for you and try to work something out.
What kind of evidence do you have that Mom's money was spent on Sister's family? This is a serious accusation and if you have reasonable cause to believe it, you can report your suspicions to APS.