Court Appointed Solicitor to act as Power of Attorney - Fees

Saigongal

Apologies - I have also posted this in category Marriage Relationships and Family but I figure that may not be the right one... but there doesn't seem to be a category to fit this one. In fact I have been concerned that this topic has zero on search engines when I am sure it must be a concern to many! 
Context - In Feb 2019 the Court of Protection made a Solicitor of their choice the Deputy Attorney for Property and Finance for my step-father (Z). He and my mother were living in the same home, and my mum was his carer. The Deputy allowed my mother control of the joint account, but took control of Z's sole accounts. As mum and Z were living together and shared all costs, all expenses came from the joint account managed by mum and there was nothing for the Deputy to do beyond look at Z's bank statements each month. We had no contact with the Deputy until October 2019 when my mum contacted the Deputy to ask to use Z's funds to pay for home-care as Z now had dementia and his mobility had decreased and my mum was having ill-health and required treatment so could not care for him. Mum's illness escalated, resulting in Z going into a care home for respite during mum's treatment period, and the Deputy authorised these payments and ensured they were made - Z's savings were not high, but just exceeded the upper limit for free care. The Deputy made her annual visit to Z in March 2020.
Issue - Z passed away earlier this month and as executor of the will I asked our family solicitor to manage probate as my mum is still ill. My solicitor has come back to me with concerns that the Deputy has submitted costs that seem rather excessive. The bill is running into £ thousands and that's only up to November 2019. They have yet to submit their full bill even through they told me they were ready to submit to their annual accounts to the Court of Protection for approval. What has been submitted is simply a statement saying 'for Professional Services', and appears to be around the level of £1,000 per month, plus 20% VAT. There is no detail as to what these professional services involve, be it letters, phone calls, reviewing bank statements, etc. My solicitor tells me that the Deputy has asked if she can simply approve what they have billed without it having to go to the Court of Protection for approval.
I have searched on line but can find little guidance in the way of expectations of behaviour or contact of Court appointed Deputies with clients, or regarding fees that they can charge.
Questions - 
Am I entitled to request detail on the bills to see what they did for the money they are billing?
What is the role of the Court of Protection in this?
Has anybody got any experience of this situation, or can you guide me to any documentation that may help me understand what is happening and what I can do to ensure that Z's estate is not frittered away needlessly on inflated Deputy bills? 
Thanks

Malthusian

Pedantry alert - a Deputy of the Court of Protection is a Deputy and not an Attorney. Your step-father had presumably neglected to make a Power of Attorney, which is why he needed a deputy. But once someone has lost capacity they are virtually the same thing so let's move on.

You would expect a professional deputy to be extremely expensive. Why did your mother not apply to be the Deputy? If she couldn't or didn't want to, why didn't you? The time to object to the high cost of appointing a solicitor as deputy was back when your step-father needed a deputy. It may be spilt milk but it will also help add context if you can tell us why he needed a professional Deputy at all.

That said, your solicitor should be in a better position than me to say whether their fellow professional overcharged to the point the Court of Protection might intervene. As executor of the estate I would say you are perfectly entitled to ask the deputy for an itemised bill.

Keep_pedalling

It is very rare that a professional deputy would be appointed while a venerable adult  adult was being cared for at home, so it is unlikely that anyone on here will have had a similar experience.

As executor you should certainly demand a break down of the deputy’s costs and challenge them through the firm’s complaints procedure and then through the SRA if you do not get a satisfactory response.

https://www.lawsociety.org.uk/for-the-public/using-a-solicitor/complain-about-a-solicitor/

I don’t think the CoP are going to be much use to you now that he has died.

If he had little in the way of savings is his estate actually solvent?