I need my brother-in-law out of my house but it will impact on his children

Pull out, rent a room. What's the bet his brother manages to find a job

Why would you want to be with a man who has no respect for your wishes, no care for your home, is fine with putting a financial burden on you and walks all over your boundaries?

Spoiler: this isn't going to happen.

You kick out the brother and he resents you.
The brother stays and you resent your partner.

Decide what YOU want and just get on with it.

If you make him homeless, he will get (I think) emergency accommodation. I think it’s a choice for your dp between him and you. You have to tell the bil and your dp. The children can go to their mum’s/childcare.

And the way you are going to play it when you have the conversation is that WE are wondering if you have contacted the council about accommodation as WE are moving and there will be no room as WE need the spare rooms for hobbies ( invent some )

Where are his parents in all this? What are they doing to help? Also, have you considered that evicting him might benefit him in terms of housing support. Could you frame it that way to your partner.

If your BIL is not working who is feeding the kids at your house ? And with what ?

Has BIL made a good faith effort for find work or is he being a lazy bugger? That would determine my approach.

If he's generally a good guy in a bad situation and has been trying to find work then I'd see if I could help him get a job somehow. Job hunting is time consuming and if he's got toddlers running around distracting him then with a bit of additional help he might be able to find something.

If you feel like he's taking the piss then perhaps a more aggressive approach is needed.

Just you feeling unhappy with your house trashed and you paying for the food bill and no doubt everything else. So the joint niceness hasn’t happened to you. Tell your dp enough is enough. You deserve better. Get your own place by selling this place and buying/renting on your own. They are freeloaders.

Back out now. Please.

But it isn't a joint decision. It's only you who wants his brother gone. So you're going to have to play hardball unfortunately.

Yet you don't seem to mind your own growing resentment. Just tell the bil to move out. he needs to learn to take responsibility for himself. sounds like he makes stupid decisions and expects everyone else to bail him out. He's a parent, he needs to provide for his dc.

Unfortunately you are going to have to do the dirty work. Ask him what his plans are when you guys move, because he is not coming

Definitely need an ultimatum. And stick to it.

He won't get help unless he's made homeless. He needs to call the local homeless helpline and arrange a place for himself and his kids. What a ridiculous living situ. Your partner isn't husband material, I'm afraid....

The piss people will take when they have you ‘stuck’.

They are paying you no mind, because they know you can’t afford to live on your own.

That is not a good position to be in, and especially not with a partner who doesn’t value your feelings or mental well-being.

I’d start working on that as a priority.

And if you gave your DP an ultimatum, ie it’s you or the brother, how would that pan out?

I know it should be an obvious choice, but so many men are really weak when it comes to family members

if your DP won’t grow a pair and tell him to move out,then what’s stopping you telling him, OP? It might be DP’s brother, but its a jointly owned house, so you have every right to do this.

Are you afraid that your DP would undermine you, if you did this?

Realistically your dp and his db and dc seem to be a package deal now. You need to base future decisions on this, especially binding financial ones.

Is your dp working, and how are the finances split?

Well you're fucked then really aren't you? Because he will move with you, your partner doesn't give a shit how you feel and you'll be stuck with him.
Maybe you need to reconsider your relationship as a last resort.

One thing to remember is your buyers soliciters will expect the property empty of tennants / family and yourself

so this could be difficult if your DH refuses to kick his brother out or if brother refuses to move

This is ruining your relationship

you Need to tell your dp this

you should be having a wonderful kid free time. Do you have sex like a carefree young couple? (Sorry but it’s an indicator of how far his brother has plunged your relationship into the shitter)

I would consider halting the new house purchase and asking dp to buy you out so you can leave him. Can your parents help you buy an alternative property on your own?

I would tell him that I am pulling out of buying the next property. If you are not expecting to move for a few months then presumably you haven't yet exchanged contracts. I would tell him that his brother has 6 weeks to find somewhere else to go, and someone else to mooch off and at that point it was either him or me.

If he's not out in 6 weeks then I would be ending the relationship and telling your bf you are dumped and I'll be moving out and expecting my share of the property.

It's the only way he's going to listen.

Time to have some stern words with DH... new house, new home life!
I would raise concerns about the brother living in a spare bedroom wit 2 small children... it's not healthy, both physically and mentally for all 3 of them.

Have the adress or phone number for your local council / housing department ready and suggest the brother to present himself as homeless with the children in tow. This can be followed up by a letter confirming the sale of your current property....

Show him how much his "D"B costs. Tell him where the money could go instead - Something DH really loves or much needed renovations on the new house.

... I am sure there are other points you can raise.

In the end, if DH doesn't come to his senses, have a long chat with yourself and decide if this is the kind of relationship you want.