In my grandmother's case, it's a run of the mill Bank of America rewards credit card (I had to burn goodwill just to get this far, so we agreed to stay with her preferred bank). Before my mother's death, when I was supporting her financially and her having had a long history of and struggle with addiction, I used TrueLink (which I cannot recommend enough, and had found them here on HN) as it allows you control which category of merchants the payment method can be used with and has strong reporting capabilities on spend.
https://www.truelinkfinancial.com/
https://www.ycombinator.com/companies/true-link (YC S13)
If you come across this comment and need advice in logistics for caring for loved ones, contact info in my profile.