Can anyone offer any insights on deciding who gets what from our parents’ house? There’s a lot of stuff and my siblings live 9 hours away.

Absolutely do NOT store anything for anybody.
Tell each of them to come in a pickup truck.
Set FIRM deadlines for getting their items and for the estate sale, else this process will NEVER END.

Be prepared for at least one person to get upset over something ridiculous. (a friend of mine tells of a HUGE fight among his aunts over an old butter churn)

I had a relative die recently. Her grandkids were her only heirs. NONE of them wanted to speak up and say "I want X or Y." It was like pulling teeth to get any of them to even show up at her house to pick up anything (she didn't really have anything valuable like antiques, crystal or silverware). Then, after X and Y were given to another grandchild, all helllll broke loose!

Meanwhile, there were numerous heirloom quality things she had sewn and crocheted that none of her grandchildren wanted. There were also boxes of old pictures from when she was a child. I delivered those items to her siblings and they were ECSTATIC.

I don't know what conversations you and your sibs may have already had about some of these belongings, but two things came to my mind.

The first one is don't assume anything. For decades, my DH lived with guilt and apprehension that, when the time came, he and his sibling would be fighting over a particular item from the family home. The sibling relationship was already strained and it certainly seemed plausible that this could happen. It was a good-quality item handcrafted by another relative, but I didn't think it was worth the hard feelings and I planned on advising DH to just let sibling have the item and get on with life. Well... sibling didn't want it. Period. No strings attached. All that time, worry, emotional energy, discussion and the sibling didn't bat an eye at DH taking the item. That said, there were a few other rather oddball things that sib DID want badly and we would never have predicted that anyone would want those things.

The next thing was that, with your siblings living further away, please don't get involved with storing the items/things for them. It sounds simple enough to hang onto something for someone or to arrange for paid storage, but I've seen it lead to very hurtful misunderstandings as to how long you agreed to store it, what was to be stored, who's paying the storage fee (if there is one) and also how and when the stored items would get delivered to their respective homes. And, there are also those folks who want something stored or "set aside" for them and they never ask about it again - let alone come and get it. So how long do you keep it for them? My advice is make it a clean break and stay out of the middle.

You wrote: "...I’ve never paid myself a dime...even though my husband I have had to take numerous days off work and numerous weekends to stay with them in the hospital, take care of financials, take care of properties, etc..." Sounds like now you agree with the lawyer and should have kept track of your hours and paid yourself.

It's worth going through your old datebooks and putting all that time and mileage into an Excel spreadsheet and keep track going forward. You are not being an a$$hole for taking an inventory of how much caregiving cost you during 12 years. You and your husband may be surprised by the number.

Ask the lawyer if you can take a lump sum from the sale of the home and/or its contents. That way, you are compensated and, in the future, her estate can be divided evenly.

My father and his four siblings had the best solution that I've ever seen: Each person drew a number from 1 to 5. They began in the living room and, in turn, each of them "claimed" their favorite item. They continued, in turn, until there were no more items that they particularly wanted, and then they moved to the next room.
Each person was always free to trade with another for an item that they had missed claiming, but there were to be no arguments, since each could have claimed it when they had the chance. At the end of the process they put their own items in a special place and invited my grandmother's best friends to come in and look at what was left. If someone wanted a certain china pattern because they remembered the wonderful meals my grandmother served on it, they were welcome to it. Some very small, but especially nice, items were arranged on the dining room table and all friends who came to the house were invited to select a piece that would remind them of my grandmother. Anything that was left was given to charity. 
I stood in for my father and selected items for him, since he couldn't be there, so I saw the process work from start to finish. Four siblings (plus me) from all over the country, over five days, going through a fully-furnished three-story house, yet there was not a single argument or even a cross word! Each item chosen evoked fond memories, people were telling funny and poignant stories, and what could easily have been a really terrible experience was actually made enjoyable and a tribute to my grandmother's long and eventful life.

I would tell them x day is the day we plan on getting rid of stuff, 9 hours isn’t a long drive if you really want moms China set or some of dads tools. Because the estate sale people are coming x date. Mom needs the money for her care. Sorry can’t hold stuff @ my place don’t have the room.

one thing I have learned in life is families will get bitchy and gossip sometimes, if anyone really complains I would just tell them this needs to be done now because mom needs the money for her care.

All this inventory and photos suggestions is way too much work for OP to manage. Either sibs come for what they want or find a way to get house empty.

After our parents passed away, my brothers and I decided that no material possessions were worth more than our relationships. So we each went through the house and put stickers on what we wanted. When we both wanted the same thing, we either bartered for something else or simply let the other one have it. My problem as Executrix is all of the stuff no one said they wanted originally. That was not quite true as we got down to the nitty gritty of going through drawers and closets. So we went through it all over again in cycles. Have patience and be good to one another.

The best suggestion I have heard, it worked for friends....

Put slips of paper with numbers in a hat. If you are three siblings, then the numbers 1-3 go in the hat. Draw a number, that is your order to pick for the first 3 rounds. Then all the numbers go back into the hat and repeat.

This does mean everyone would have to be there, but with Skype, Zoom, Whats Ap, Facebook Messenger, it can be done remotely. They would each have to have a proxy, but it would be best if everyone could be on site, wear masks, have lots of hand sanitizer and work through it.

Before you start have a plan for the things no one wants. Also do not accept the responsibility of moving, storing or otherwise handling any of your siblings things. That can cause more unrest than the divvying up. I know of three people who are storing bulky furniture from estates for people who live out of town. One person is going on 4 years and really wants their storage space back. Another stopped receiving cheques to cover the rental fee at the storage company.

If some one has their heart set on Granny's China, or Dad's old tool box, and no one else cares, it is easiest to deal with those things first. But is someone is saying she wants all the crystal and china cabinets, then no, she can choose one set from one cabinet, and when her turn comes around, she can choose more.

I had a terrible experience with this, including a secret visit to the residential care center by a “caring relative” to “harvest” LO’s jewelry, then accusing ME of doing it, then admitting (bragging) that it had been done to “be fair”.

Be ready for some unexpected bad acts. If someone in the “family circle” decides he or she is “entitled”, there’s really no way to protect your mother’s rights from it.

I understand what you are feeling. Some of this should have been decided years ago. One thing to think about, what would any grandchildren want? I'm sure there were many family meals served on those china plates. My mom now lives in a retirement home, she is getting ready to go to Assisted Living, she has Dementia, but she became a hoarder. When we moved her, our movers warned us that she had so much stuff it would never fit into her apartment. So we had to get two storage units and my garage, which took up so much we could only park one car. I have two sisters, who live in different states, who are not involved, (who do not have children either) they dont talk to my mother but want all the oil paintings. Well I bring home about six to seven boxes at a time from the storage units and purge! I have 3 boxes, one for trash, recycling and donations. I did find love letters to my father, I'm keeping those for my daughter, so I suggest you do need to go through drawers and boxes, there could be important papers or memories. I know its hard, I work and have my home, so I manage by the six or seven boxes. As the caretaker, I feel because you do the work, you need to reward yourself with the one item in the house. Fair is fair. don't let your siblings guilt trip you into giving items up. I suggest you separate the items, for example, if there are 14 items of interest and 4 of you? Everyone gets an equal amount, draw numbers for the extra, but you get that extra piece. Remember the oil paintings? My husband said to me, if they want them, they will pay the shipping up front, because we know they will never pay up. When I closed my dads house the cost of shipping just one oil painting was 85.00!! I also suggest having a garage sale, we did and never told my siblings, it was extra clothes, kitchen items, extra chairs, etc. We shell out any extra monies for my mom, I take her out, pay for her hair/pedicures to be done. During Covid, I would just take her for drives by the lakes, even though she has no memory of those outings. Those who do the work and time spent, should be rewarded. Put yourself in charge and don't apologize.