I have four DC, aged between three and ten. I returned to work last year after taking eight years out. Like you, ZERO family support, and no friends I would feel comfortable asking to leave even one DC with, let alone four. So a very similar situation.
My career is in IT so it's reasonably well-paid which helps.. the downside being is that most IT jobs, especially when applying, require you to be fulltime. Ideally I would be part time. I went back to work because I was bored and depressed, and right now our costs are about the same as my salary - I basically gain a pension and that is it in real terms. It will get cheaper when the youngest is in school but it's hardly going to be a life-changing sum.
Here's what we do:
- a cleaner
- an after school nanny five days a week (this is very cost-effective with four DC - cheapest way)
- nursery for the youngest three days a week with the nanny for the other two days so she gets a bit of freedom as the nursery does not have a big garden
As we have a nanny, part of her responsibility is to do the children's laundry and keep their bedrooms tidy. That takes a LOT of the pressure off us combined with having a cleaner too.
We're also very lucky in that DH can work from home on a fairly ad-hoc basis so long as he doesn't take the piss. This means he is usually able to cover for child sickness, although that doesn't happen very often any more, not like it did initially. I think they've caught most things now! Also a nanny will often take a child when a nursery will not.
My work has core hours of 10-4.30 and I work 15 minutes away. This means I can still do assemblies etc so long as I work later that day.
I take a week of unpaid parental leave every year which means I have an extra five days for things like appointments, school meetings etc. And days when the nanny is on holiday.
We also use holiday camps on occasion for when the nanny is away in the holidays, otherwise the nanny does full time in the holiday. This is totally normal, lots of nannies are fine with after school only and then full time in the holidays, although I won't deny it's a huge pain working out fair ways to calculate holiday allowance when you have such variable hours! We use a nanny payroll company which helps with the pay.
It's a juggle, I won't deny it, and when the childcare breaks down (nanny sick, or a child properly sick) it can get stressful. But we muddle by. It won't be this hard forever and my career is now well-established again. Most importantly, I have my sanity back and a better relationship with our children as a result!
I never thought I would be able to find a way back to work but I did. It can be done - just tackle one problem at a time otherwise it feels insurmountable!