Nervous but about to take the plunge. I teach, but am about to quit my teaching job!!! Is there anything I'm not thinking of?

Things to consider: Total devil's advocate here, because I would probably do this for my mom too as things stand right now because we do normally share a home with her when she is not taking care of my grandmother so I can see this being a possible scenario for us down the road.
1. Vacations: you will have to hire someone 24/7 @ $25 /hour if you want to take a vacation. (From Mom's budget)
2. Mobility: what is her current level? When my SIL moved in with FIL, not even as his caregiver, he went from nearly 100% independent with nearly all independent ADLs to nearly 100% DEPENDENT with nearly 0% ADLs in the span of a year. Because she was his daughter. He saw no issues with asking more of her. And as he did, he relied less on himself and lost his independence entirely.
3. Privacy and alone time: when your entire life is 100% dedicated to caregiving you may find that there is little time (or in fact energy) left for yourself or your spouse.
4. Resentment: what seems easy peasy right now is because you are not doing it 24/7. To both you and your husband. But will he or you feel the same when you don't have time for each other? My mom is currently caregiving for my grandmother, who is experiencing SHADOWING as part of her dementia. She cannot handle being away from my mother for very long even though my grandmother is quite independent. She is very anxious when my mother is away. She does NOT like to share my mother with other people for too long, even my mother's own grandchildren. She's ok for short spans of time but when she is ready for my mother's attention she pouts and acts out. Are you prepared for the impact this could potentially have to your marriage? Is your husband aware of things like this occurring and getting worse in dementia and that if she fixates on you, no one else will do? That it won't be him sharing you with her, but in many ways her sharing you with him? At least it may feel that way.
5. Loss of retirement income
6. Loss of autonomy: that one may seem an odd statement, to you, it's just going from one just to another right. But it's not, not really. You can quit teaching. Its a lot harder to quit your mother once you start this. Are you prepared to hire full time caregivers and live with her and see her disappointment that you aren't doing the caregiving if this doesn't work? Or if you ultimately have to move her to an assisted living facility?

These are just some of the things that come to mind.

Are you giving up a pension?

What about SS credits?

Have you looked at what your retirement funding will look like?

Have you ever availed yourself of further training in classroom management or in behavioral techniques? Or peer to peer training? I am a life-long ed person.

Most of can learn how to manage a classroom if we don't assume that children should respect us from the outset.

Please think about what your mom's need will be in 5 years, when you are 5 years older.

Your profile says that your mom has Alzheimer's/dementia, so as you're aware she will only continue to get worse and your days of "easy peasy" will be short lived, so enjoy them while they last.
Being a full-time caregiver is the hardest job you will ever do, and the little pay the state will give you should really give you pause. If you thought being a teacher was exhausting and stressful, you ain't seen nothing yet.
And yes, please hire with moms money someone to give you some much needed breaks, as you will not survive this caregiving journey otherwise.
Don't get me wrong, I think it's nice that you want to take care of your mom; I just think you still have your rose colored glasses on, and am afraid of the day when you take them off and see what you've gotten yourself into.
So just don't give up your teaching license quite yet.
Best wishes.

Choupette - you asked: "Anything I’m not thinking of or seeing?"

My answer: I think you should find out the hard way like the rest of us.

After quitting your job, and caring for your mom 24/7 for a few months or a year, you will find out every reason why you shouldn't have quit your day job and taken on a 24/7 job.

Whatever we tell you know now will pale in comparison to what you will learn first hand on your own.

What about benefits? i.e. health insurance, vacation pay, sick leave. And consider your Social Security and pension. And your mom’s needs will increase. She may be easy now but that won’t always be true.

Ideally, kids get better as the school year progresses. Your mother will do the opposite. She'll get progressively worse, will require round-the-clock care, and you'll be dealing with feces, bathing, and eventually a bedridden woman who can't be cared for by one person. You won't get any sleep, and your health will suffer. Your internal radar will never turn off because you can't just go home and sleep.

If you can afford the loss of income, Social Security credits, privacy, and sleep, go for it.

I took care of my parents for two months when my dad was dying of cancer. Both were relatively easy to care for, but by the time my dad died after six weeks, I'd lost 10 pounds and hadn't slept more than two hours uninterrupted because Mom had dementia and would get up to go to the bathroom and to tell me Dad was dead when he wasn't. I was a jibbering wreck by the end.

My husband and brother thought we should move in with Mom so I could take care of her in her own home, and I shot that down immediately. I loved my mother more than anything, but I knew she would die sooner in my care, my marriage would end, and my health would suffer further. I also knew that my husband sure wouldn't help my mother wipe herself or bathe her, so every caregiving task would be on me to accomplish. It is literally a 24/7 job, and no one can work those hours without dropping.

Do you have any long service leave or ability to take some time off to trial?

It may work well for you, but re-assessing every 3 months may be needed.

Caregiving can turn into a slippery slope quickly! But also, it may be very rewarding for you.

Just have an escape plan.

There are a lot of people who will tell you that this is a horrible idea but I did something similar and it was a win win for my mother and I (for the first few years anyway). Definitely plan for regular respite, try to fit in some me time every day as well as your weekends.

The biggest difficulty I faced was how and when to stop being a caregiver - I thought I had a good plan in place but I ever realized just how physically frail and dependent people can become and how long they can continue to live that way. I held on way too long because I didn't want to drop the ball with the end in sight, but one day I realized I had nothing left to give, my emotional tank had run dry. I called mom's case manager and told her I was done, and mom got a priority respite bed in a nursing home and then transitioned to full time placement. She lived another 18 months beyond that time; wheelchair bound, almost totally immobile, needing to be fed her pureed meals and in general as needy as a new born. I spent a lot of time in that nursing home and she was far from the only one ekeing out her final days in that way.

Also, what you do mean by "reducing our financial footprint"? Like reducing your carbon footprint?

You think you need less money as you age? Spend less money as you age?
Oh boy! How wrong you are.

How about a different teaching job?