The 4th child really is no more trouble than having 3, my 4th is the cutest and coolest of the bunch. He just gets on with things, there is always someone older around to help him, and show him how to do something.
We have a small income 21k that my dh earns, I work pt as and when I can, tax credits help us survive. Yes things are tight but we don't go without, I shop for good quality food. My kids all wear good clothes.
I store everything to hand it down, my children treat toys and the house with respect as they know we can't afford to replace things.
We don't go on a summer holiday but we do go to center parcs the week before xmas as a huge xmas present to us all.
Space is limited as we only have a small 3 bed with 1 bathroom but we are all very organised and manage. We have 2 cars, 1 old runabout and an old 7 seater. The days of flashy cars are long gone!!
There is no way 1 more child causes us any more money problems than having 3 did, we have to live to our means, we always pay our bills on time and never go without, we may have to wait for things but then we appreciate them more.