The absolute way to tackle this is "what are we spending our money on"
People who declare themselves broke (not being dramatic, I just do some work alongside people who are low income and starting businesses) often have no money, but it's not the money they have necessarily, it's what's left after they've made the spending decisions they have. Some are essential, some are not.
So, you've got £4600, less mortgage and car of £1300. That's £3300.
(I'll go estimates) water £40, gas and electric, £180, c tax £150, TV licence £14, prime Netflix £15, internet and broadband and TV package £70, phones £50, two lots of car insc and tax £120, groceries toiletries household £800, house and contents insc £25. Fuel £100.
That's another circa £1600. Add in another £200 for someone needing clothes, someone needing trainers and it being someones birthday. £1800. Then there's bigger things, the washing machine needs replacing, one car needs a service, the other needs new brakes, the boilers gone, something's broken. These can go from £100 to £1000. Let's average it at £250 a month over the year. So that's just over £2k.
Take that off your £3300 and you've got somewhere around £1100-£1200 left.
That sounds like a lot. With your £200 into savings, you should have a minimum of £900 left. And this is where the frittering that could really make a difference happens. £900 sounds a lot. But. 900 x 12 / 52 = £207 p/wk, which suddenly doesn't sound as much. Friday takeaway for 4? £50. Now it's £157. Extra bottle of wine for Saturday night? £20. £137. Everyone off to the park/generic outing on Sunday? Parking, £5, lunch on the go, £40. It's now down to £92. Husbands 3 coffees during the week, £15. £77. Both kids to the cinema/into town with friends (parking/tickets or a tenner to spend) £25. And you're down to £52. Someone needs a haircut, and with the parking, the hairdresser, the quick coffee on the way back, that's gone.
When you've identified what your frittering is, focus on that. With a bit of bill comparison you can reduce your essentials, but unless you're currently being totally shafted, it won't be a life changing reduction. But when you tackle the frittering that eats up the £900 you should have left, that's where you'll be able to make big changes.