A few points. Firstly the capital settlement is affected by the value of any pensions which aren't mentioned.
Secondly, tax credits should be nearer £500/month for someone working 16 hours/ week and earning £800/month. You can check this out @ www.entitledto.co.uk
Thirdly, when looking at maintenance the capital settlement needs to be considered. It's proposed wife will have an income of £1,500 -1,800 plus husband's contribution of £1,000, leaving him with an income of £3,250. However, if she gets 80% of the equity and he retains a 20% interest in the FMH the husband will need to pay a mortgage of about £1,200/m more than his wife to buy an equivalent property.
On the other hand, if the capital split is 50:50 and the husband pays between £1,200 to £1,400/m global maintenance there is little difference in their incomes.
Lastly, when one spouse has a disability and the other a reasonable income there is every possibility that SM for life would be awarded by court.
Disabled living allowance has not yet been awarded and is in any case, for our youngest ( adopted) son.
Ex works 2/3 days a week,largely by choice, not necessity.
She lives in the FHM 5 beds, and had previously stated that she would move out, but now will not.
Your post is correct in the mathematical calculation, however, the basis of it is flawed. Why should I work 5 days a week, take on 43% childcare duties, and then give money to someone who doesn't want to work, who needs the money to fund a larger than neccesary house, and is happy to have babysitters and a house cleaner too?