Any advice / guidance on child arrangements pls ?

[Tinkerbellx]

Hi
Im divorcing my ex after 25 yrs marriage for unreasonable behaviour.
We have 4 dc.
2 adult - 1 independent the other at uni
2 dependants aged 13 and 6.

I have initiated and paid for the divorce petition which he has signed .
I have initiated and paid for a solicitor to do financial settlement .

We have nothing in writing re children and its now been 2 years .
To keep it short ..

He left to live at his parents 60miles away - free of charge . Joint decision so he could save to rent somewhere decent near to us after a couple of months .

I managed to save before him ( hes a spend thrift and I now realie bone idle ) and so I offered to put deposit down on a property and help him set up ect .( Also knowin after 25 yrs he wouldn't manage this himself it would be me or another woman )
He just wasn't interested .
Says he cant afford it but I know he can.
He spends a lot of money taking new gf away, has new clothes, brand new Mercedes fgs. Now how he spends his money is none of my business but it really upsets us when he insists hes trying to move nearer to the dc. I wanted a 50/50 split .
He still tells them hes looking for somewhere and its been 2 yrs .

In the 2 years he has them overnight on average once a month .
I e mail and message him every single Monday without fail inviting him to arrange contact / see them/ visit them/ ect and am always ignored .

When he does see them its at short notice when hes passing .
When he has them overnight its not easy . I pack everything, he comes after lunch and brings them back 24 hrs later usually not having had tea or baths or homework . Or he cancels at the last min.
I always agree and say its ok to call in if he s this way . We usually eat together and its amicable .

He has a gf who he sees every weekend and she lives local to us ! That's upsetting because he tells the dc its too far to drive and that's why hes cant see them , but hes here anyway .
Since hes had new gf he also ignores his phone from his ds from fri eve until mon morning without exception .

He didn't visit when they were ill in hospital twice, doesn't come to school events ect .I always invte him but its wearing me down to be honest .

The dc know ive tried everything so im not worried there , because unfortunately he has been known on several occasions to tell them I am the reason he cant see them .That I stop him .

The sad thing is he was a fantastic dad and when hes with them still is .
Ive had him here Christmas day and some birthdays and its good when he shows up.

While im sorting the divorce and finances I was hoping to get something in writing re contact but have no idea what to ask for . He wont have them more than 1 night a month but I think he should be seeing them more .
He says his parents are too old to tolerate them more than this but that because hes paying me maintanence he cant afford a deposit to rent somewhere ( ive offered to pay )

I cant force him to but want something in writing just to be absolutely sure that if the dc ever question this when theyre adults its there in writing that I tried to encourage not discourage contact .
My bf says hell never change whatever I put in writing and that I should just take whatever when ever he will see them.
Its just better for them to have something on the calendar to get excited for and plan and look forward to iykwim.
I think im just ranting ! x