AIBU to not want my brother living in my flat long term

Hes your brother. Unless there’s some bug back story about how mean he is to you, etc, then I don’t understand why you wouldn’t help him. I’d say the 10mibth suggestion is reasonable. You want a lodger abd could end up with a horrible person. At least this would be 10mibth a with someone you know.
Why would you need to talk about politics with him? You would still be able to live separate lives surely, your own meals, friends etc.
I agree with your parents.
I really hope when my DC are older, they wouldn’t think twice about offering help like this to each other. I pray they have a relationship where they care and want to help each other

it is YOUR flat
does not matter if they helped you, why do they get to decide on YOUR flat and your life.
have you explained how you feel to them?
If they care they won't expect you to live like that.
What can they do if you say NO?

You either have him there feel uncomfortable
or you don't have him there live with the guilt.

You are not being ungrateful. It is your flat and you have the right to make decisions about the flat.

Your parents helping with your deposit doesn't give them the right to dictate who lives in the flat. If you don't feel able to say a flat out no then be firm with what you can offer. If that's 4 months then say he can stay, but only until end of January. Put it in writing so no-one can later dispute that's what you said. If he hasn't found somewhere by then, he'll have to move out into a flat share with others. His wants (not living with strangers) do not override what you want in YOUR property OP.

After 4 months he should have a deposit to rent somewhere surely? If he's looking to buy, I doubt he'll have enough for a deposit in London in 4 months, unless he has a brilliant salary. Then you have all the time needed for conveyancing etc and it could be a year before he's ready to move out.

Are your parents going to help your DB with some of his deposit?

Get a female lodger now, then it is a done deal. Cite money reasons

then the brother cannot move in

then in a year you can maybe live on your own for a bit (if you can afford to) and enjoy the peace

Absolutely not. Your home is your safe space and you need to be able to relax when not working. You have chosen not to have a lodger for a reason.

He's older than you, been working longer, higher earning than you, why has he not bought his own place yet? Been sharing with a girlfriend? Now he wants to use you in the same way.

No, no, no.

I would say that I value my relationship with my brother too much to risk it by living with him and therefore it’s not happening.

If your parents are angry, let them be angry. You need to prioritise yourself.

No. Keep saying no to both parents and brother and block if you need to. Their attitude is what really gets to me - they will be a nightmare if you give into their bullying.
This is your house and you are able to say who does and doesn't live there.

Your parents did make it possible for you to stay in London (which is expensive).

I would say yes - if

A/ a contract for 3-6 months + houserules
B/ rent - market's rent no discount.

He should be treated like any ordinary lodger do no misunderstandings.

Or pay your parents back the money.

Will your parents help your brother to buy too?

you are very wise to say no now, you can see the problems that your parents and brother are not willing to see as all they can see is a marvellous solution

I have 2 adult children - they have always got on and are very close but I would never expect one to house the other for more than a couple of days

The suggestion of having him stay only Monday to Thursday and going back to your parents at the weekend is a good one. Explain you think it will damage your relationship rather than strengthen it.
It would be a hard No from me for that long.
The other thing is to get a cleaner in extra as that's the main cause of resentment in a shared house.

I would let him but this is based on my picturing my own family relationships. I personally would rather share with a sibling than a stranger but that’s because I know it would be fun and I appreciate every family is different.

You don’t say that you don’t get on but that you’re worried about your independence and privacy. That’s a strange one as I can’t imagine how your brother staying will stop you being independent. Will be expect to chaperone you around or stop you from doing stuff? Are there other cultural things at play here where he won’t want a female relative being independent?

Also, what are your privacy concerns? Has he got form for invading this or reporting back on things you do to your parents etc?

Presumably they didn’t give you the deposit money with strings attached? Si they din’t have leverage.

You need to show them how upset you are and that this ciuld make your relationship with DB really bad.

I think its best to say no full stop because once he's in you will never get to decide when he leaves.

There's a wedding coming up in my family on a Saturday. A relative from out of town asked to stay Friday-Sunday but sorry, I've got "plans" on Friday night and can only host them on Saturday. Its the most I can bear to be honest.

I think saying no and pointing out to your parents that it has disaster written all over it, that they know you don't get along and do they really want to strain your relation to the extent you will be unable to spend time together as a family at Christmas (or whatever family celebrations you might have together)?

If you can't say no, you need to find a way to make it work for you, though. I would have felt exactly the same way about my brother in my 20s. We didn't get on. Seemed to antagonize each other without trying. Had different politics. Etc. 20 years on and we get on a lot better. We haven't exactly changed, but we seem to be able to give each other a bit of grace when we don't agree. Would a sit down chat with him about how you're concerned and you aren't prepared to put up with arguments or disrespect help? And put a 6 month limit on it since that's his estimate. If he thinks he can save the money in that time, he will then have the money for rent after even if conveyancing stretches over.

Your parents helped you with a deposit, that’s an amazing gift.

But it’s a GIFT.

They don’t own the property or pay the bills. They don’t get a say.

You need to lay down some boundaries here and commit to them.

Your brother is ‘expecting’ to stay with you - nope nope nope.

This will end in tears.

If he needed a place to stay for a few weeks in between housing, I would think you might be unreasonable to turn him away. Months is ridiculous. He needs to rent.

Would it be feasible compromise that he can stay but only as commuting lodger e.g. he travels into work from assumingly your parents and stays Mon- Thurs night only

Also after he settles in will there be hybrid working as that could help with the part time with you and the rest elsewhere?

Just a thought

How much did they give you? Can they give the same to your brother?

The problem is THAT deposit. Money never comes without strings attached. They will use that to guilt you. I doubt he’d want to live with you for that long anyway, he’s a single man in his 30’s. How can he bring home women/men with his sister in the next room? You could always be a horrible room mate, leave a mess, don’t tidy, be a pain to live with.

Have your parents helped your brother with cash/deposit?

I do appreciate it's hard to stand up for yourself when under pressure from family but if you don't, where does it end? How many other people will they guilt you into taking. Will they veto future partners? Moving plans? Your parents have already called you cruel and greedy - can't get much worse, don't buckle. Keep repeating 'No, that doesn't work for me'

Your brother is a man in his 30s, you are not responsible for him. I agree with the above poster, it's got disaster written all over it. To assume he can move on at a discounted rate at a time scale to suit him gives a more than a whiff of entitlement.

How does your brother not wanting to share with strangers trump your not wanting to share with him?

Unless your parents gave you the money for the flat on the understanding you house your brother, you are fully entitled to say no. If there were terms attached to the contribution they should have made it clear when they gave it to you, so you could decide if you were happy with them.

He's perfectly capable of getting a flat share. If you let him move in, getting him out will be a nightmare!

Maybe they can pay for a flat for him

Your parents helped you with buying it but they don't get to say who you have live with you. Stand firm OP. If your brother is earning ok, he can stay a shorter time that you find reasonable or go rent. Don't feel guilty - your parents shouldn't gift with caveats.