If you had the choice between using mom's funds to put her into an ALF (that offered care for dementia patients), with the understanding that her funds would be depleted in about 4 years, and she'd be transferred to a Medicaid facility until her death (which in the case of her mother was over 10 years)...or use a portion of her funds to build a small home on your property, (with the construction geared towards providing comfort and ease til her end of life at home), investing her remaining funds to continue to build equity and be able to provide hired home health care for her once it became necessary for 24/7 care, and become her caregiver, which would you choose? And why?
So mom had a stroke and was taken via ambulance to the local hospital. It took each of us more than an hour to drive there. By which time mom had nodded agreeable to many questions, including "do you have diabetes?" ( she didn't and doesn't. But it took us a while to get the order for insulin dc'ed).
We decided shortly thereafter that mom was going to need to be 10 minutes from one of us. She's now in a nh near one brother with the most financial resources, the most flexible job and PoA.
As to the money, there are certainly continuing care communities that you can buy into that will guarantee lifetime care. There are states where ALs have Medicaid beds, especially after several years of private pay. When mom was discharged from hip surgery, the discharge folks took a careful look at her Financials with us and recommended for rehab a place that was also a long term care facility that accepts Medicaid after private pay. Mom has been there for 2 years now, and at 15,000 per month, her money will last about another 2 years after we sell her house. It's all working out so far. It's a two hour trip each way for me to see her and 5 hours for our youngest brother, but it was a good decision.
Best of luck and light to you.
Don't spend a lot of time worrying about what will happen when her money runs out. There are so many possible scenarios for five years in the future. She could develop health problems requiring a move before that, or her dementia may progress to the point that her surroundings have no meaning for her. There is enough to worry about now without trying to figure out something that may never happen!
Having said all that, if Mom did not need 24/7 supervision, I might have a different opinion.
You should think very carefully about trying to care for your Mom on your own. She could live for many years but the dementia can progress very rapidly. I would hate to see anyone go to the trouble of building a house or apartment for a loved one only to see the person is hardly aware of their surroundings in coming years.
There are long debates on this forum about home vs facility care and you should read through some of them. Most people regret trying to go it alone. I agree with Cwille's first post on this thread. I think she captures the issue very well reflecting on her own experience.
A person with dementia cannot live alone beyond the very earliest stages. Even a house on the same property is "alone" so that may turn out to be a very expensive option -- building the house and then paying for in-home care. I couldn't leave my husband alone while I went grocery shopping. My sister had to get someone to come in to stay with Mother when Sis went bowling.
The other factor is that dementia -- dementia of any kind -- gets worse. It is the one thing you can absolutely count on. You mother may need the level of care provided in a nursing home in three years no matter where she is now. Even if her money holds out to pay for the ALF, her health may not. And it may not allow her to stay in a private home, either. My mother stayed in my sister's home as long as what she needed was "assisted living." That lasted 14 months. Mom is in a nursing home now, and thriving. She, too, wasn't social before going there so we are surprised and delighted she never misses bingo or a sing-along or live entertainment or a baking session or crafts. Sister had a hard time getting her out of the house to even her beloved beauty appointment. Now someone wheels her down the hall where she gets her hair done happily.
My best friend just wrapped up the sale of her mother's town house and she was saying this will pay for her mother's ALF for another 3 years. Her mom is now in the hospital and may never recover sufficiently to return to the ALF. No matter how carefully you plan, you cannot anticipate all future events.
Whatever you decide to do, discuss it with an attorney certified in Elder Law. For example, how will Medicaid look at using Mom's money to build a house on your property. You still need to decide what is best for your mother, but make sure your decision is carried out in the most advantageous legal manner.
Is your mom in need of care now, or are you just looking ahead? Does she have any income coming in that would stretch her savings further such as SS, or a pension? Is she the widow of a wartime veteran? If so, the Aid and Attendance payment for a widow is now about $1,100 per month after her assets are down to a certain level. There is info about this on this site. Does she own her current home which could be sold to help pay for care?
In my opinion, your plan to build a small house is much more risky than an AL. What if you spend a significant portion of her money on the house and then something happens to make it impossible for her to continue living there? A sharp decline in her mental function or a broken hip could require either a move or 24/7 in-home care, which would quickly deplete her remaining funds. Then, if Medicaid is needed you may have a problem with the money spent on the house being seen as a gift to you. It is not as if you could sell the little house to recoup the money since it will be built on your property.
As for her own mother having Alzheimer's/Dementia, it doesn't mean that your Mom will have the same identical issues.... she could instead have inherited aging health issues from her own Dad. My Mom developed serious dementia just a month ago and prior to that she was doing pretty good memory wise, it was a head injury that caused her to go into accelerated dementia. So anything could happen in the future.
As of last month my parents were in their own home, alone, with Mom trying to do all the cooking, cleaning, laundry at 97 years old, she refused any type of outside help be it caregivers or cleaning people. With her stubbornness came falling. The last fall was very serious and she is now in long term care.
Dad now has 24-hour caregivers at my parent's home because he is a fall risk. I am a senior myself so I am limited on what I can do. It is costing Dad $20,000 a month for licensed bonded caregivers from an agency. If I had hired independent contractors, my Dad's home insurance would need a workman's comp rider which isn't cheap. Dad is now asking about the cost of Assisted Living which would be close to half the cost of around the clock caregivers.
Why not opt for an addition to create an apartment in your own home and charging your mom a reasonable amount of rent as compensation?