Help with claiming benefits.

Hi there

Im helping my sister out with PIP form (new claim) as I know how much of a nightmare it can be.
Im using all what I have learnt from all at B&W and the pip guides that are provided which is priceless in my opinion.
PIP is for my sister’s husband and they both had to give up work due to his conditions making it impossible for both of them to work, as she is now his un paid carer(wife) 24/7.

Im confident by following your guides he will get Enhanced on both components as he has Alzheimers & Angina and mobility issue.

The husband is in the process of claiming ESA contributions based support group.

I would like to ask what else can be claimed for them both?

I understand that some benefits claimed go against others, so what is the best route to take?

So far their situation is or will be soon :-

Both unemployed now due to unforeseen change in circumstances.
Home Mortgaged, low mortgage though.
Not much savings its easily under the threshold.
PIP ER both components(husbands) new claim tbc.
Esa contributions support group(husbands) new claim tbc
Wife is an unpaid carer.

Can he claim disability & Enhanced disability premiums at all?
Does she have to claim UC too, or will it knock out another benefit?
Would claiming carers allowance make matters worse?

Any help is much appreciated