How much can my mother deduct from her taxes for Assisted Living facility expensive?

You really need to get breakdown of what services are provided and whether they are under a doctor's prescription as "medically necessary". Most assisted living facilities are used to this question: many will give you the breakdown. But here's why you need professional tax advise.
From Publication 502 IRS website:explains Medical Expenses on Schedule A.
"Nursing Home
You can include in medical expenses the cost of medical care in a nursing home, home for the aged, or similar institution, for yourself, your spouse, or your dependents. This includes the cost of meals and lodging in the home if a principal reason for being there is to get medical care.
Don't include the cost of meals and lodging if the reason for being in the home is personal. You can, however, include in medical expenses the part of the cost that is for medical or nursing care.
Nursing Services
You can include in medical expenses wages and other amounts you pay for nursing services. The services need not be performed by a nurse as long as the services are of a kind generally performed by a nurse. This includes services connected with caring for the patient's condition, such as giving medication or changing dressings, as well as bathing and grooming the patient. These services can be provided in your home or another care facility.
Generally, only the amount spent for nursing services is a medical expense. If the attendant also provides personal and household services, amounts paid to the attendant must be divided between the time spent performing household and personal services and the time spent for nursing services. For example, because of your medical condition you pay a visiting nurse $300 per week for medical and household services. She spends 10% of her time doing household services such as washing dishes and laundry. You can include only $270 per week as medical expenses. The $30 (10% × $300) allocated to household services can't be included. However, certain maintenance or personal care services provided for qualified long-term care can be included in medical expenses. See Maintenance and personal care services under Long-Term Care, earlier. Additionally, certain expenses for household services or for the care of a qualifying individual incurred to allow you to work may qualify for the child and dependent care credit. See Pub. 503.
You can also include in medical expenses part of the amount you pay for that attendant's meals. Divide the food expense among the household members to find the cost of the attendant's food. Then divide that cost in the same manner as in the preceding paragraph. If you had to pay additional amounts for household upkeep because of the attendant, you can include the extra amounts with your medical expenses. This includes extra rent or utilities you pay because you moved to a larger apartment to provide space for the attendant.
Employment taxes. You can include as a medical expense social security tax, FUTA, Medicare tax, and state employment taxes you pay for an attendant who provides medical care. If the attendant also provides personal and household services, you can include as a medical expense only the amount of employment taxes paid for medical services as explained earlier. For information on employment tax responsibilities of household employers, see Pub. 926.

I would check with the IRS or with a CPA to see what is deductible and what is not.

Last year my Mom was in long-term-care and my parent's CPA was able to deduct that cost. My Dad had in-house caregivers while my Mom was in long-term-care and that was also deductible.

Now this year my Dad is living in Independent Living with some assisted living options, so the CPA said we will revisit those cost for next year's income taxes... some could be deductible, others not. He said the guidelines are always changing.

They are ABSOLUTELY deductible. There are criteria such as an inability to perform at least 2 activities of daily living (ADLs) or cognitive impairment. If you do a computer search on the question, you will get many reliable sites that explain this further.

Here is another thread where this is discussed, the answer seems to be maybe, at least partially. It depends on whether the AL is documented as being medically necessary ie your mother has dementia.


www.agingcare.com/questions/assisted-living-self-pay-monthly-premiums-tax-deductible-152900.htm?cpage=1

I don't know if any of the AL rent money can be deducted. Most of the money is considered as going toward rent, food, and cleaning. I don't know what portion of it would be medical. It might be hard to tease out.

Skilled nursing facilities are deductible as medical expenses, but I don't think AL is. I hope someone with more knowledge than myself can give you a more certain answer.