If your mother is of sound mind (no dementia / no Alzheimer's) and she is willing to allow someone to act as her legal agent for financial matters, housing issues, and other day to day business matters, then she can grant a power of attorney to whomever she chooses.
Assuming that she would want it, you can be the one she appoints, making you her "attorney-in-fact." But I wonder how this could work with you moving away and her remaining here? Even in this day and age with computers and the Internet, most business and governmental entities will not work with attorneys-in-fact unless it's face-to-face and they can actually see the power of attorney document in their own hands. That could mean that you may have to come back to where she is living in order to adequately help her.
Another option is for your mom to give you power of attorney as I have described above, but also to name some other person locally near your mom to act as a co-attorney-in-fact. It'll be your mom's option, but the language could be drafted such that the local person cannot do anything without your consent. That way you get to make the decisions from where you live and the local person here locally can then go to the bank, pay bills, or take care of all the things for your mom locally which you cannot do remotely.
I recommend you contact an attorney who practices elder care or who focuses on wills and estates. The lawyer can assist you and your mother in drafting up the appropriate documents, but your mom will need to go to the lawyer's office and sign them in front of a Notary Public. It may also be a good idea to have the final documents recorded in the county auditors office. The estimated cost of such legal services is more than $500 but less than $1,000.00.