What should I charge

I would have thought buying your house, rather than you moving into your DM's would mean you'd need to sell your house when your mother passes away to share an inheritance with your siblings.

Unless you have the cash to buy out their shares without having to sell, but that's not clear.

If that's not the case, even if you buy your house now, you will have to move from there anyway (which I understood you were keen to avoid).

Think very carefully about this. You may het home and realise her needs are more than you can cope with. Are your siblings on board with helping care for her. There are worse things than residential care. If the fees are as high as £6k. Month. It suggests she has very high care needs.

I think you are putting money ahead of your mothers needs , to me it reads like you and your siblings don’t want her going into a home because you can see it eating up your inheritance .

You can’t pay yourself for being an Attorney. You can spend money for her benefit, so it’s arguable that you might get away with the amount the Council would have to pay for the amount of care that they would provide, ie a max of 4 x 30min visits a day at about £15 per hour. But you should take advice on this.

I don't know if you posted before or another poster in similar circumstances Either way, my reply is the same
Get legal advice as buying property with someone else you'll be caring for is very complicated
Think very hard about your DM care needs The practical is very different from the theoretical

I disagree with posters who think you saving rent is reward enough.
if my DSis gave up her work to care for DM I’d also want her to get paid at least the minimum wage at 60 hrs per week. Care home is easily £5-6k a month and you are massively contributing towards your DM’s happiness. You aren’t just helping DM, but the wider family as well by being on the spot.

Money can't ever be ignored. However, if you are seriously contemplating selling your mother's house with a view to investing in yours, then you do need legal advice.

I can see why this looks fine - your mother's house would quickly be sold if she were going into a care home, and you have every intention of sharing the money according to her wishes after her death. However, it is still possible im afraid that despite all your efforts she may need more care than you can offer, at least for a short time, and will need to pay for it. It's also possible that something could go wrong with developing or selling your house. Dont get into a programme like this without legal advice.

OK. In that case could your mum rent out her house, move in with you, and pay you the amount she receives in rent less the house bills, plus perhaps £1k of her pension? That way your rent is covered, you get a small amount on top of that, your mum still has spending money, and the legal situation is much more straightforward.

My sister did not want my mother (vascular dementia) to go into a home, but she had to in the end after mum broke my niece's leg pushing her over a chair.

So the house my sister and kids lived in was sold from beneath them to pay for care fees anyhow.

Please take legal advice over any house purchase. Would make more sense to modify the house she owns to make it suitable for you all.

I’d also consider moving into her house with her otherwise once she passes the other siblings will want to sell that house and where will that leave you?

homeless, no income and no job

regardless of where you live you will find yourself in the above position which is quite frankly dreadful

I mean what do your siblings expect you to do afterwards?

Checking my understanding:

Your mum inherits half of a £700k house from your dad (and anything else?). There won't be inheritance tax to pay because she is his wife.

You want to buy your bungalow, selling your mum's house to facilitate that. The remaining £375k will then be invested (?) or bonds bought to provide an income, on top of the £1450 she already gets. Does she claim attendance allowance? If not, can she start (I think you can claim on her behalf with POA)?

So when she comes out of hospital, will you lose the £1200 a month at that point, is that right? But gain £1000 in not paying rent once the purchase is completed?

And you'll be on duty 24 hours a day, 5 days a week? Does your mum wake up in the night regularly (to the point you'll be unable to sleep?)? If not, do you have a plan for if she gets to that point i.e. room for a carer?

Would you be able to claim carer's allowance? I know it's not much but worth thinking about.

What will your plan be when your mum passes away? Hopefully she has a happy remainder of her life but I'm just thinking if you inherit e.g. £100, will that enable you to buy anyway?

I can see I've just asked questions rather than giving an answer. I think it depends on lost income, what you can claim to top your mum's income up, what other costs if any you have, and how you're going to manage after Shree eventually passes away.

You and your mum neednto see a solicitor.

I wonder if your mum can pay all household bills from her income (council tax, gas, elec, water). You will probably get around £4,800 attendance allowance and on top of the rent you're saving, the bills you're not paying, that does make for quite a contribution already. I think you're saying you'd not have the 1200 a month if you looked after your mum, is that right? The attendance allowance and her paying bills will likely account for about £750 of that £1200. If your mum chose to give you any extra per month of our her income or what will be left when she sells the house, I guess that's up to her?

I'm not sure why you are suggesting buying your rented house, when there is a mortgage free one sitting spare.

You should move in with your mum, and she pays for food and bills. It sounds like you'd still have your part-time income, plus your pension, so there's no need for anyone to pay you, especially as you said you'd do it even without the money.

You'd then be living both rent/mortgage free and getting your bills paid as well as food, saving yourself a small fortune. Care home fees also saved from you being there. Everyone benefits.

When your mum sadly passes away, the house should be shared equally between siblings.

I wouldn't make any far-reaching decisions until you've seen your mum away from the drugs/infection/hospital roundabout. You need to be prepared for your mum to need a good deal of care, beyond anything you're anticipating right now. She may not, of course, but I think you need to be aware of how your daily life is likely to pan out before you enter into any agreements.
And I'm sorry about your dad's prognosis. It's hard to make good practical decisions when you're going through all of this.

If she's showing signs of dementia, moving house may make things deteriorate. The extent of my mum's dementia wasn't apparent until she was taken out of her familiar environment. Then she went downhill rapidly. Is moving in with your mum in her own home an option?

Are you happy for your house to be sold to realise your siblings' inheritance when your mum dies?

If so, I think free rent and possibly your mum also paying bills would be enough compensation and keep things clear.

You will be getting £250 a week that you save on rent.

Also, you might get into an issue with inheritance tax - if she buys your house has she got enough separately to cover the IT so the house wouldn't have to be sold to cover it?