POA and conflict of interest?

We live in TN. Mom prefers to be on her own and has been in apartment until this recent hospitalization with pneumonia and atrial fibrillation. Her dementia is very mild, with occasional memory lapses but has been functioning, driving herself to shop for,groceries and to church (both within 5-10 miles of apartment). I feel she needs time to recover and gain strength but not sure she needs long term in facility BUT sister has notified apartment owner that she is moving, had belongings packed up & will probably sell or give away everything except her bedroom furniture which is in her room. Yes, I suspect sister will take advantage of access to financial situation. Would not tell me what she is charging mother and there is no signed contract!
Yes, she does have 3 or 4 other residents who pay her cash so there is no taxes or record. If mother needs to be on a facility, she would probably prefer to be in familiar surroundings (she previously owned the ALF)
We are joint POA but I live in another town and I don't trust her. She can sign my mothers name exactly as I've seen her do on documents before.
I just want to be sure she doesn't take everything my mom has and then kick her out, like she did my grandmother when all,she had left was a little social security check!!

What does your mother want?

There are two different issues here.

Is it a conflict of interest for your mom to be in a facility that your sister own, if your sister is poa? That depends on the laws of your state and how the pie is worded. You really should ask an attorney. Perhaps mom's AL contact would need to be modified. I know of a situation within my family where an elderly mom was in a NH owned jointly by her and her son. She wouldn't have wanted to be anywhere else.

The second question seems to be, would my sister, as POA, have an easier time defrauding my mother if she were a resident in sister's facility?

Do you mistrust your sister? Does your sister defraud other residents?

Beachgirl, regarding your Mom's Power of Attorney, are you and your sister of equal power on said document, or is your sister the "primary" and you the "secondary"?

Does your Mom need Assisted Living? You mentioned Mom has "some dementia", thus she might do better in Independent Living facility if she is mobile and can still do things for herself. The cost is would be less.

Now, if your Mom goes into Assisted Living [not a Nursing Home], and runs out of money. Then what does your Sister intend to do? Most Assisted Living facilities do not take Medicaid [if Mom goes that route]. Usually Nursing Homes will accept Medicaid.

If there is a facility available, try to find one that has Independent Living section, plus Assisted Living section, and an Assisted Living/Memory Care section. This would be much better for Mom. Thus if she makes friends within the community, no matter where they or Mom move within the community, she can still see them :)

Who is the "financial" Power of Attorney"? Are you afraid your sister will skim money from Mom's checking/savings account?