Does anyone know how to keep dad at the assisted living facility? Says he's walking out on Friday and going home.

Babs, if you have guardianship, YOU and not dad determines where he lives.

Talk to the faculty about this issue. As an AL, they may not be able to keep a person who wants to leave, against his will. You may need to move him to a secure memory care unit.

Have you consulted his doc about meds?

I think that sooner, than sooner than later, you will most likely be looking into a locked unit.
If the AL he is presently at happens to have something like that, the transition may be easier than having to remove and transfer him.
Your first reaction, if you are anything like me, is that he is functioning at a higher level than the other residents of the locked unit, and in some ways that may be true, but if he has been diagnosed with dementia, you have been granted guardianship, and he has no perception of his inability to manage his ongoing needs, you can begin to assume that his need for a secured, structured environment is somewhere on the horizon, and in some situations, it is easier to head in this direction earlier than later.
Under the terms of the guardianship, is there any language that requires you to provide a safe, secure environment for him?
If you place him now, in a locked unit, you will at the very least have a certain amount of time to figure out what to do next.
If his prior living arrangement was NOT possible as a consideration, it is not fair for to him OR YOU, to spend time figuring out ANY REASON OR PLAN for keeping him there, so start thinking forward to other scenarios that MAY work for him and don’t look back.
My LO has been in a well run MCU since last June. I visit often, and whether I leave in tears or marveling over how much she is still her old self, I am content that she’s monitored, safe, and lovingly provided for.

You are his guardian, it is your choice where he lives not his. He has been declared incompetent, so he no longer has a say or will be able to contest.

If he walks out they will come looking for him and then require that he be placed in the memory care wing on lock down. Or they will tell you that he needs to be placed somewhere else.

You are in charge, not him.

I would make it clear to him that he is not going home now. You can tell him, if you think that he is capable of absorbing it (I would suggest their social worker with you) that if he cannot abide by the rules and stay in his facility he would have to move into memory care, which is a locked unit. I would tell him that it is a good deal different in that it is more like a hospital with more staff, locked door, and often a roommate. Those are the two choices. There is, sadly, no third choice of coming home because it is no longer affordable.
It is time to do the tough love thing.
Often the facility suggests you curtail visits during this adjustment period because the elder sees you as "a way out" as someone he or she can manipulate, knows, and knows HOW to manipulate.
Only suggestions I have, because if he insists on this then he likely IS looking at memory care. You can tell him that along with being much less nice, it is also much more expensive, and if his money runs out during his lifetime he could end himself in a quite not-nice circumstance that you would be helpless to fix for him. Remind him you know how tough it is to go through this one loss after another thing, but that you will continue to do the best for him that you can, and that you love him, and that you don't EXPECT him to be happy about it, because not everything in life is about happy.
This will not be easy. Think of a toddler that is given too much control and ends up in meltdowns constantly with the fact they can win, then don't know what to do about it. It needs to be more certain for him. More set in stone. No argument. Just the simple loving facts told as kindly as you are able, with sympathy, over and over and over when he goes "there".

My father was a very stubborn man, even before dementia and even when it was unreasonable to be so very stubborn. I am my father's daughter and inherited his stubbornness in full measure; however, as a child I decided I did not want to be stubborn about snap emotional decisions and cut my nose off to spite my face as my father sometimes did. As an adult, I listen and consider everyone's views then make my decision and stick to it unless or until someone brings up a new view/fact/position to consider. I do not change my mind just because someone else doesn't approve or agree with my decision.

As my father's dementia worsened, I became the "only person who can deal with him", primarily because he knew I was as stubborn as he was and would do what I said.

When Dad didn't want to go to MC and told me he wasn't going, I told him yes he was. "You can go the easy way in the car and walk into MC with your dignity or you can go the hard way drugged and strapped down to a gurney by removal attendants. Either way you are going. You need the level of care the MC can provide and I think you will like it there once you get used to it. I would rather see you walk in but one way or the other you are going to MC." I showed up at an appointed time and followed the car while my estranged brother drove Dad to the MC. Dad walked in to his room where he was surprised to find it contained his favorite rocking chair and was decorated with photo collages of family and collectibles. He did adapt and even like being there.

I don't know your Dad's personality or whether his dementia allows him to remember things enough that talking to him would do any good. If you think it would work, I suggest you talk to Dad about what's going to happen if he walks out of the AL. That he has no money and no keys to his house; his picture will be on the news as an elderly dementia person the police are looking for and when the police find him he will be taken to a hospital to be evaluated and held until a locked MC facility can be found, or maybe a NH if an MC isn't available because he won't be able to return to the AL after "escaping". Emphasize that you will have little to no control over what's happening once the police are involved. Ask him to please not do this to himself. You want him safe and someone available to see to his needs and right now the AL is the best place for him. Good Luck.

It sounds as if you feel your father is suffering from some form of dementia or is otherwise a danger to himself and have begun the process to force a guardianship. Until he's declared it may be difficult to force anything but perhaps you can talk him into staying for a longer vacation by telling him you've already paid for the month and if he leaves you will lose the money. You could tell him his home was infested with mice while he was away and the exterminators are getting them out while he's on vacation or some other small lie? If nothing else works and he does walk out of the facility with no way of getting home that would probably be enough to get the local police to pick him up for evaluation which might have the result of forcing the declaration a bit quicker than the usual route. I hope everything works out for all of you.

Ann Reid seems to have the most logical solution although nothing's really a solution. It's difficult no matter how you look at it but keeping him in the facility is your best answer I went through the same or similar situation with my mom I was fortunate that the hospital had determined she needed 24-hour care so it was a decision that I did not have to make but once she was in the system she's in a great place and I couldn't be happier for her she actually calls her room her home and when she goes out to the activity room all rooms she has a blast with everyone there the mother that I've known all my life would never have tolerated which she is now but she is doing remarkable she is truly my inspiration. Good luck with everything and I hope all goes well for your dad and for you.

Babs, you are paying for this with Dad's money, right?

What will you do when he refuses to leave his home with the caregivers? Have you been in touch with the local police who might need to assist?

Not an area of expertise of mine, but can you request an expedited hearing or a temporary restraint to keep him there until the case is reviewed, given the circumstances? I have read enough to know all these issues of health directives, DPOA, guardianship seem to vary by state.

Babs, it will be so much easier if YOU can accept the fact that YOU are now your dad's parent, (the turning point for me). Try to see him as you would a toddler or kindergartner. You have compassion for him, love him and want to protect him and care for him. There's no expectation of a toddler or young child making wise decision for their own care. Make the necessary decisions without inner turmoil. You only want the best for him, so make those decisions and explain them to your dad in clear, understandable words without talking down to him. State what will happen. He's done nothing wrong, but cannot make wise choices anymore. Put in place all the safety plans for care necessary and do not ask permission from him. Think toddler; what do I say? Do you want to go to the bathroom? No. "It's time to go to the bathroom." No room for argument, or a "No" or "Later" from him. Just a fact. Best wishes.