I have never worked anywhere that has cost that much.
Typically care will cost 600-775 per week and the NHS will fund the nursing element of care at approx 186 per week if the person is deemed to require nursing care.
The costs are;
Gas and electricity. The homes are very large and have lights on 24 hours per day, heat on for at least nine months of the year, a TV in every room, WiFi for all the alexa/Google assistants/ laptops and ipads, not to mention the PC for the management staff.
Maintenance on the building and structural repairs.
Equipment, hoists, stand aids, individual slings, pressure cushions, air mattresses which need replacing regularly due to constant use.
Profiling beds, bariatric beds, commodes and shower chairs, wheelchairs.
Company vehicles to be maintained and insured for days out, trips to the GP/hospital etc.
Food and drink, three meals per day plus homemade cakes, snacks around the clock. All diet fortified with extra vitamins and nutrients to prevent malnutrition.
Laundry services from wear to wear plus bedding, towels, curtains, cushion covers on a regular cleaning schedule.
Cleaning contractors for the industrial laundry machines.
Carpet cleaners, vacuum cleaners, cleaning products, soft furnishings, dining room furnishings crockery and cutlery all needing to be replaced at signs of wear and tear.
Staffing;
Nurses notwithstanding as the NHS funds this as discussed earlier.
Staff will be variously;
Finance/HR
Care staff
Activities staff
Cleaning staff
Laundry staff
Maintenance staff
Gardener/s
Cook/s
Kitchen assistants
The home will be staffed 24 hours per day obviously and this constitutes the largest outlay.
Most homes are private companies or third sector.
Head over to companies House and avail yourself of their most up to date accounts if you are interested.
CQC will detail the company name of whoever runs a particular home.
That may be more beneficial than asking people on mumsnet.
Carehome.co.uk will give you an estimate of each home's fee ranges.
Not many run in to £1000 per week in my experience of the sector.