(image from en.wikipedia.org)
We start with what we have got [the balance in the bank and any cash], add on what is expected in the next week, and have a total from those figures. Then I look at what demands there are on that money: quite a few this time - taxing and MOT for the Fiesta [£205], and the bills that are due between now and the 7th June [£250.60], and my NI bill [£68.90].
I take that second total away from the first, and it leaves me with a decent amount. BUT I have to deduct the amount I still need to put into savings from that [£550] and that leaves us with just short of £95 a week for the next three weeks. And that is for all discretionary spending - food, fuel, activities, donations, medicines, gardening bits, gifts, toiletries, etc....anything that is not a direct debit or a previously considered bill.....
Out of that weekly amount I know that I have to give the FH £4.50 for his lunch club, and the YFG will have a £10.50 piano lesson two weeks out of the three [one is half-term] and our church giving will also come out of it [usually £5]. That leaves us with £20 spent most weeks before we actually start eating and driving the car. I know that I put diesel in my car last week so it won't need any this week, but it will be in need of a top-up next week, so that will have to be taken into account.
Given that I have fairly good store cupboards, I think that our food spending could be covered easily by about £40 a week, so I am fairly confident that the savings goal will be achieved. But all it needs is the Fiesta to fail the MOT to put a spanner in the works, but we will take each event as it comes and just wait to see what happens. It runs well, is well maintained and looked after and there are no strange noises, so fingers crossed!