I'll try and keep this brief - I've also posted in chat.
I've got 3 DCs - 4 (just started full-time school), 2 and 3 months.
I've been offered an amazing part-time temp contract by someone I used to work with. The salary is great so will be able to afford nursery/cleaner/food delivered etc.
DH works 4 days a week so 1 days childcare is covered. Other day will be nursery/after-school club and grandparents have offered to do the third day. (I'll be able to work from home for at least one of these days).
The job is great, I know I can do it but it will be hard work. But it's only for 6-9 months and I feel like it will 'buy' me a bit more time at home by keeping my CV up-to-date.
I think I've got a lot of my bases covered by basically calling on grandparents/DH and friends. DH is very supportive and keen for me to do it but I don't think he has any idea of the impact it will have on him as I've been a SAHM mum for 4 years and do most things in the house.
I really, really want to do it! But will we all cope?