To not want my MIL to move into our annexe

I grew up with my grandmother living with us. I nursed my mother before she died. I love the idea of multigenerational living and deeply regret not being able to provide my daughter with that as she grows up.

But even I think you need to say ‘Hell, NO!’ to your DH and MIL or you WILL become her carer and you WILL resent it and you WILL have marital problems.

I wonder this too- was it your husband's idea?- if so, there's your answer.

Why are you buying a house with an annex? What were your plans for it?

Like others I also wonder what the purpose was of buying a house with an annexe in the first place, unless it was to rent it to someone else?

Realistically MIL was always going to see this as an opportunity to ger her care needs sorted, but in your position I'd forget any possible rent and look for something else

Edited to add I also agreed with this: he isnt going to make his mother homeless is he so if she stops paying nothing will happen- you're stuck with her. The separate front door also makes no difference- she will be at your door constantly
Better, surely, to avoid the whole situation in the first place

I suspect the annexe means that even if this doesn't happen now, it's in the ether and will inevitably come to pass unless you're absolutely hardline on it - or buy a different house.

If his mother is going to be evicted/homeless and can't find a private rental, the council should deal with it and find appropriate housing. Dh can help with that.

My husband and I are financially contributing 50/50 to the house purchase and my husband has already made it clear that MIL would have to pay rent to live in the annexe. The annexe has its own front door and there are no interconnecting doors between it and the main house

This is completely irrelevant - he isnt going to make his mother homeless is he so if she stops paying nothing will happen- you're stuck with her. The separate front door also makes no difference- she will be at your door constantly.

As a PP has mentioned, if she does pay you will then have to pay tax on it, you will be subject to tenancy laws and obligations and council tax etc

I also suspect that this timing is very odd and that this is something they have cooked up together behind your back.

You will also need a license ( in my borough). Gas safety certificate, electric safety certificate, carbon monoxide testing machine. Enegy efficiency rating. You will be a landlord and need to adhere to all the rules that involves. And realistically is he going to evict his mum if she doesn't pay. Oh and all her visitors will think they can just pop in to you after because after all your family.

It's a hard no from me and I really like my in-laws. However, I like my privacy and peace more. I also wouldn't want to spend all my time minding someone else. As she gets older and needs care who will end up lumbered with the work?

Of course not. This sort of thing can't happen by stealth just because her rental issue times with your house purchase. She can find another rental. It'd be different it was all planned and you all got on and wanted to live together. But in this case, absolutely 1000% not. It's your home and not hers to move into. Your DH's views on your family are actually not relevant. You do not have to live with your MIL full stop. You don't need any reason or argument. If he wants to live with her, then he doesn't get to live with you. Not Your Problem.

If you are renting it:
Income needs to be declared through a tax return.
Need to be registered for council tax as it sounds like an operate dwelling. If it doesn't already have a separate reg you might be in for shock when you move in anyway as some councils wait until a change of ownership to raise council tax. https://www.mumsnet.com/talk/property/5071380-council-tax-for-annexe
Need gas, elect certs, epc etc. The fact that it is family makes no difference.
Need to declare it to the mortgage people as well

Pull out of the house sale now, what was the reasoning for buying a house with an annex?

Same. You'd be an idiot to buy a property with an annexe in this situation.

For the love of God, do not do this. I've seen this play out a few times with friends (both an annexe and a spare room situation). It has been an utter nightmare. Both times boundaries were supposedly put in place- the older person agreed to give them some space as a couple. Didnt happen. Every day/night the relative would come downstairs or to the house wanting to chat and watch tv with them, would say they were lonely, didnt want to be on their own, wanted to be included in everything etc They basically ended up having zero privacy as a couple, literally everything they did, they had to do with the relative in tow- even going shopping. Then, when the relative became frail it was just expected that the woman would help with care needs - on top of childcare, working, household stuff etc.

One of those couples is now divorced and the other is still together but living separate lives. Dont underestimate the toll resentment will take on a relationship.

who broached the subject of the annex? MIL or your husband?

It all seems very coincidental, have you seen the section 21 papers?

I’ve just spent two months living with a relative of my husband’s due to a house chain issue. Even with the fact that it was for a temporary period it was not easy for anyone. I would advise you to nip the idea in the bud as soon as possible and be very clear about it. No “perhaps” or “I’m not sure” sitting on the fence comments, say a clear no.

Ooh. I would let that sale fall through and buy a different house without an annex, tbh.

If you don't have one then your frail about-to-be-homeless MIL can't ask to live in it. Rent and council tax are not the issue here.

100% do not let her move in!

If you're super set on the house with an annexe then tell him you want it converting to a games room, a library, storage etc - anything other than a house for his mum.

With his attitude to your parents I wouldn't be allowing his mum to move in with you, especially when as PP have said the support will be coming from you in 99% of cases.

Hard no from me. She’d be much better off looking at LA over 55s accommodation. This tends to be available more often than other accommodation as there is a decent turnover of people. It’s much easier to get a cleaner/ carers/ district nurse and even a Gp visit etc as they will be seeing other residents. This will help as her care needs increase. If you let her move in, you will get dumped with everything, you’ll end up back on here at some point when she has been admitted to hospital discussing refusing to have her back as you are completely burnt out.

If he wouldn’t be willing to have your parents live in it then it would be a definitely no for me.

there isn’t a compromise in this situation,

Erm, are you entirely sure you're not being set up here?

My parents came to live with us so say for six months of the year, they had a seaside holiday home . That quickly changed. They were with us for 5/18 years. At one point I gave up work to nurse my father in his final six months. It went on for three and a half years. We used up our savings, I lost my career and our children suffered. We were on the bones of our arse. He refused a home and I was not the only child. Nobody helped.
Fit sixty somethings turn into totally reliant eighty somethings. You'd never get her out. Buy something smaller. I wouldn't wish elderly care on anyone.

Even if you loved your mother-in-law to pieces and she was in perfect health it would probably still be a bad idea because, well it just is isn’t it

Why does DH have a problem with your parents? How solid is your marriage (he doesn’t sound great based on what you say)? How much faith do you have that he will shoulder the burden of any care? Do you actually like your MIL? Would it be a positive for your kids to have her around?

My parents had this issue with their parents. They both decided that if one set wasnt allowed to move in then neither could the other. It's the only fair way. If your husband wouldnt tolerate your parents moving in (which he clearly would not) then neither should his mother. Thats hardly fair is it?

Not being unreasonable. You'll end up being at best, the person who helps her every day and organises her care etc at worst, her full carer - are you ready to help this woman with her intimate care every day?

Why are you buying a house with a man who doesn't tolerate your parents? Are your parents that bad? Now might be the time to really have a look at your long-term future.