is there someone who can help you oversee your maid? if yes, you can consider getting one.. note that other than maid expenditure, you will also need to pay for your eldest child's school fees..
otherwise, you have to consider childcare (pick one near workplace) or nanny (able to pick up late) option..
if your job requires you to be overseas often, will your hubby be able to handle them alone after work? if not, nanny may be a better option as can nego to let them stay overnight.