To leave the marital home in a mess

Can any of it be sold and would make you some quick wins in terms of space cleared and cashed for your new home?

Things like prams and baby equipment you could sell ridiculously cheap on Facebook marketplace and it would give you a good chunk cleared as it's all bulky.

Or offer it up to a local babybank / family hub / charity / family in need for free but they collect it.

Also any of your stuff you've not used and are happy to say goodbye to you could again offer up bundles of super cheap or free on FB. I wouldn't leave MY personal clutter for him to clear. The kids stuff and stuff dumped by his family I'd feel less guilty about.

Our area we often put stuff outside our house with a "free" sign on it, and it's always gratefully grabbed by someone. If you don't drive that might be a good way to clear some stuff too.

Pull all the toys out of the shed and put them outside your house with a sign saying free. Pop a post on Facebook and you will be amazed at what goes. Then hire a very large skip!
I don’t think it’s fair of you to leave the house in the state you describe when you say a lot of it is yours. What if the landlord comes to check up on the house when you come off the tenancy - could the mess jeopardise him keeping the house?
You keep saying that you’re setting up from scratch but surely you would take things like the crafts which are yours. I think walking away from mess you contributed to when your children will continue to visit is out of order.

Who created the mess?
You said its mainly yours and the kids stuff and your ex husbands stuff.
You should tidy and clear your stuff at least.
If the rest is joint and kids mess and you are amicable and your kids will be spending at least 50 percent of thr time there then I do think you should at least help to get it into an ok shape before you go.
Do some dump runs, take some stuff to charity shops.
You can hire a declutterer who will come and do it for you and take some stuff away to the dump too.

I agree, why the angst about it now?

In the kindest possible way if this is the house they are currently growing up in why are you wanting to sort it now you're leaving. They will be accustomed to living that way. If you are equally responsible for the amount of clutter then surely they issues won't magically disappear once you move into a new property. You're hoarding ways will follow won't they?

To be quite honest, hiring a skip is so emotionally freeing. You've paid for it, so you feel you've got to fill it to get your money's worth. Stuff you might ordinarily overthink about dumping, goes in the skip without a second thought, particularly if you only have it for three days. When it's collected and you see it disappearing down the street, you fell ten years younger - or at least I did.

And they hold an amazing amount, much more than you's expect.

I have just read your update that most of the stuff is old toys and your stuff so yes I think you need to advertise stuff for free on Facebook and ditch the rest. Why haven’t you sorted it before now?

Good point! Why worry now when it’s been like it for years anyway

You don’t drive?

let me guess, you’re moving to a rural village?

When I left my exH, I left a lot of the clutter. I don't feel a single ounce of guilt about it, but that's down to my situation. OP hasn't expanded much on her situation regarding the relationship or how it ended, other than "Ex isn’t the type to do anything much around the house except the basics like dishes etc."

My ex didn't do much of anything around the house (or with the DC) His laziness was a part of the breakdown of the relationship. I even asked him to help sort through things with me while I packed, so we could throw things out if neither wanted them. Nope. On moving day, I ended up having to go to his solicitors because they messed up the paperwork. When I got back, ex and his sister had opened some of my packed stuff, then bagged it up, mixed in with clutter, and some of the actual rubbish from his room. About 8 big bin bags, full of crap, with maybe a couple of things I had packed, in each bag. I was running out of time, and hadn't hired a van big enough for all the extra stuff as well. So I emptied the bags out, took my things out of the pile, and left it all for ex to deal with. He created that situation, he can deal with it.

So I guess it depends on what other factors there are. If my ex had been reasonable, and hadn't acted like that, I would likely have cleared out most of the clutter before I left.

You need to clear all your stuff including arts and crafts etc.

Maybe talk to ex and hire a skip, both of you clear stuff out into it?

I don’t understand why this is a concern now they’ll be living there part time, when they’ve been living like this full time up until now. No point going over your reasons for not clearing out the crap before, but I feel this may be more about having a way to still be involved in your ex’s life, than a genuine desire to clean up the former marital home.

While it will be refreshing to be in a lovely tidy place and to leave the clutter behind

wont your new place get cluttered and dump like soon enough if you’re that way inclined?

I don’t think it should be just left to you (but it sounds like a dynamic that might be one of the reasons for the relationship breakdown that’s guessing)

but depending on how well you get on now, can you suggest a week where you BOTH take time off work to sort this. Hire a skip and blast through the rooms.

You should rent a skip and get rid of stuff of little/no value that you will never use again. Sounds like you should have rented a skip years ago but better late than never I guess.

Hire a skip and go through kids bedrooms with them skipping anything they say they don't want. Take your art and craft things with you. Take a lot of the DC things if they'll be living with you, their clothing, bedding and hobby things, games etc. Clean kids bedrooms, I'd give kitchen a good clean and throw away anything not needed, before I left. If I had time I'd clean bathroom too. Especially as you say he won't do it and your kids will be using the home.

Whose choice is the split? Who is responsible for the mess and clutter? Presumably you have been living in mess all this time too so why have you not sorted through previously? I am not sure why you are feeling guilty as surely it is both of your faults if the house is messy?

Or maybe try and be a bit sustainable, the plastic toys are probably grand and could be used again?

Why not put all the semi decent stuff on pavement, and put it up on local Facebook groups, People who are interested scan message you for address.

Get a skip. Drop any pretence that this rubbish is worth money and skip everything. People will take stuff out of it anyway.

Thought the same…

Does your husband know you are leaving?

Hire a big skip, ( it’s about €150 here for the week) and start in the kitchen. That sounds appalling to be living in clutter falling out if cupboards like that. I can see why you want to get out of the house.

Have you got support and advice in real life?

It sounds as though you are responsible for virtue all of the things in the house as you say very little of it is his. It's actually sounds like a very depressing place to live in and I'm surprised you are worried about your children staying there two days a week when you are not bothered about them staying there full-time now.

You both sound like hoarders. Other people gave you stuff but you didn’t have to accept it or keep it. Take the stuff you want. Discuss with your ex whether or not he wants you to remove stuff from the house

The fact you are worrying about him not dealing with the clutter appropriately makes me think the clutter is primarily yours.

Take what you care about with you, accept the rest will end up in the tip.

There are charities that actually collect from your doorstep (lookup Anglo doorstep collections) you choose the date. Look online and start bagging stuff up. Hire a skip for anything that’s not good enough to pass on. Don’t just shove it all in a skip if it’s good enough to be used by someone else.