You should sit down with her and explain that you are going to help her. I would like to review the power of attorney to assure that its powers survive your mother's incompetence. You should call my offices, or another attorney of your choice with all of the details and for specific advise.
It MIGHT be possible to retrieve the car, and I would be very cautious regarding the care giver who already appears to be taking advantage of your mother's failing.
GET AN ATTORNEY NOW before the is even more harm and loss.
To the PROSPECTIVE client, please call myself or another attorney for your choice with more detaiils and an appointment. My PRELIMINARY answer to your question(s) is for general purposes and based upon what little information you have conveyed. It is based on such limited information that the general answer should never be relied as a reason for your action or inaction. My response does NOT establish an attorney-client relationship and such may only be established by mutual agreement, and the signing of a written retainer agreement, which will generally require payment for our services, as this is what we do for a living and, just like you, we must get paid for our work.. .
You are on the right track. If you want to ask a probate court to appoint you as conservator (to handle mom's money) or guardian (to make decisions about her care), you need letters from her doctors. You will also get preference if you are the person she named in her power of attorney. However, you should discuss this carefully with mom. When you apply to the Court they will take away mom's power, not just duplicate it (like mom did in her power of attorney). If you'd like to discuss this, or have mom discuss it with me, please feel free to contact me.
I agree with my colleagues. You may be able to set aside the vehicle transfer, if that is in your mother's best interest, based on the doctors' letters. You may need to go to court to do this, however.
Whether or not this makes sense depends on the facts. If the car is not worth much, your mother would never drive it again, and the caregiver is good for your mother, you might let this go. It could relieve you/your mother of potential liability and ongoing expenses.
In other words, this decision may not be as bad as it would appear on the surface. On the other hand, the caregiver maybe working up to something larger and your mother may not be able to protect herself. There is not enough information to say for sure.
As has been pointed out, the POA allows YOU to act. It does not necessarily prevent your mother from doing so.
***Please be sure to mark if you find the answer "helpful" or a "best" answer. Thank you! I hope this helps. ***************************************** LEGAL DISCLAIMER I am licensed to practice law in the State of Michigan and have offices in Wayne and Ingham Counties. My practice is focused in the areas of estate planning and probate administration. I am ethically required to state that the above answer does not create an attorney/client relationship. These responses should be considered general legal education and are intended to provide general information about the question asked. Frequently, the question does not include important facts that, if known, could significantly change the answer. Information provided on this site should not be used as a substitute for competent legal advice from a licensed attorney that practices in your state. The law changes frequently and varies from state to state. If I refer to your state's laws, you should not rely on what I say; I just did a quick Internet search and found something that looked relevant that I hoped you would find helpful. You should verify and confirm any information provided with an attorney licensed in your state. I hope you our answer helpful!