My dad urinates all over the place won’t change his clothes. Fights the whole family. What can we do?

If your father is still physically capable of walking, using the bathroom, and taking care of his own hygiene then he must do so. Many times in care situations the adult kids have to become the parents. On many homecare assignments I had seniors who were still more than capable of doing things like going to the bathroom (who were not incontinent) and feeding themselves, but who would insist on going in their pants and being spoon fed which I absolutely refused to do. I had one that I would give her meal to and she'd expect me to feed her like an infant. When she saw that the food was left to get cold in front of her then taken away when I left at the end of my shift, she soon realized that I was her one caregiver/companion who wasn't playing the baby game. I would not change her either. She was not incontinent. Any time I took her out (and I took her everywhere regularly) she would always tell me to help her to the bathroom if she needed to go and it was fine. At home it was a different story. I let her know straight that if she wanted to piss and crap her pants that she could either clean it up herself or stay in it until her daughter got home. With this being understood she stopped pissing and crapping in her pants. The other workers who came on weekends constantly complained about having to feed and change her and didn't believe me when I said that I don't do those things. When they started refusing to play the baby game with her she started feeding herself and going to the bathroom for them too.
Don't humor your father. Don't play the baby game with him either. Your family needs to make him understand that none of you are going to clean up after him pissing and crapping all over the house, and if such is going to be the case he will be sent to live in a care facility. Then stick to it. You said he's capable of doing for himself. The next time he pisses and craps on the couch or something, refuse to help him. You will see he'll help himself. Do not tolerate his rudeness and obscenity. There is always the option of a care facility and he needs to understand that you will not think twice putting him in one and not looking back.
He needs some tough love from all of you and if all the family is not united in making him do for himself and clean up his rude act then your situation will continue as it is until his disease progresses to the point where there's no choice but to put him in a facility.

Your family needs to get some education around MS and how it effects individuals, physically but also mental health supports they may need.

A friend's daughter was diagnosed in her mid 20's after suffering for years. Nobody believed her when she reported her symptoms because of the variability of them. Not being believed took a huge toll on her mental health.

A former co-worker has MS. Stress was a major trigger for her, as was trying to do too much. For her she could manage working 25 hours a week, anything over that and her MS would flare up and she would be off work for a week or more. She used to ride her bike to work as she gave up driving.

Perhaps your Dad is as frustrated as you that his abilities are so variable? Can you imagine knowing that your family is going to give your grief instead of support if you cannot make it to the toilet on time?

When you state "It’s like he needs attention constantly." are you saying he wants the family to pay attention to him, or are you saying the family feels he needs constant supervision?

If Dad wants constant attention it maybe that he is afraid that he may need help and no one is there to provide it. If the family feels the need to supervise him, then that can lead to other issues.

Please educate yourself and your family on how MS impacts a person's life.

Not to be snide--but I owned a rescue puppy for one week who pooped and peed all over the house and I realized I was NOT up to the task of caring for him--and so he was re-homed to a more appropriate place.

Maybe your dad needs a higher level of care than you can afford him at home. I can put up with a LOT, but using the house as your personal bathroom--a deal breaker.

This is up to you & family, of course, but he will not get 'better'. Do read as much as you can about MS--Personally, I do not know that much. Some people sail through w/o it totally affecting every aspect of their lives, some are very compromised at young ages.

Educate yourselves and make a plan for his care. Was he like this prior to the dx of MS? I mean, personality-wise. Just wondering.

It's my understanding that symptoms with MS patients, do fluctuate from day to day, so that's probably why you see him walking fine one day and not the next. Definitely sounds like he needs to wearing Depends on a regular basis, and probably time to get him in to see his Dr, so they can address his depression and the other issues you all are having. There are medications to help with the symptoms of MS as well, that he should be taking if he isn't already. MS isn't curable, but it is treatable to a certain extent. You and your family need to get educated on what exactly MS is and what it all entails, so you can be better prepared for what the future holds for your dad. Best wishes.

Tell him he needs to follow the rules by wearing diapers. Get a cat scan, and have him checked out. check for cancer... scare him. maybe that will make him rethink. MAYBE

What's the plan when Dad's MS symptoms have progressed past what can be supported in the home?

"How do you solve this huge problem?"

Firstly I believe by being realistic about his diagnosis & disease prognosis.