i don't quite understand the situation.
are there addiction problems involved with the parents.
how long have the children been taken into care.
is S>S intending to keep them in foster placements, or are they looking towards adoption.
from what you write it seems there are 4 children. would you be able to cope with that many, have you the resources and space. and energy.
i worked with a man who took in his 3 grandchildren, with his wife.
they were well off, with large house and garden in the country, and he was very fit and active for his age. he found all the grilling by S>S draining, and of course it changed the plan they had for their retirement, which was put off, he kept working, and wife was a full time mother to small children again, in her 60s. it's a lot to take on.
What is a reasonable minimum spend for an online grocery delivery??