It really is just down to discipline, if you want to save you will, at the start of the month, its a case of looking to the future and putting saving for the future above continuous treats now. Once you have savings, you won't need service plans, as you can use your savings for car/house servicing costs.
Same with buying cars. We have never had car payments, we buy nearly new for cash - with savings. But it hasn't always been like that, we paid cash for cheaper cars when younger.
We have just under 4k coming in (DH is self employed, could pay himself more as dividends but diverting it straight to his pension).
No mortgage, but we have a DS at uni, so he gets an allowance each month, as does DD at college (both have also worked but not at moment as want them to concentrate on studies). General bills are higher than yours, water substantially so. But - we have only normal TV, no netflix, prime, spotify etc, do you really need ALL those AND movie rentals? Maybe cut back a little.
Mobiles at 7.50/mth, with kids iphones bought as xmas presents (and DS pays his mobile out of allowance). DH and I have cheaper Androids. How many phones do you have between you?
We do buy coffee and meals out and takeaways, but not all the time. We take salads and sandwiches to work. We batch cook so we can take meals out of freezer in the week, when we know we wont want to cook.
We have a good pot of easy access savings and now save each month into S&S ISAs, plus SIPPs for me and kids. Payments are allowed for after bills but before anything else. We are on track to retire at 60, in 5yrs time, as the savings we make each month add up substantially.
We have had mostly summer caravan holidays, but interspersed with plenty of hotel and cottage breaks. But they come out of savings, so if we didn't have savings, we wouldn't do them. We have had 2 long haul hols, and now can afford plenty more, with kids at ages that they can appreciate them.
How old are your DC? Do you have to do Disney this year, or can you wait another year or 2. I find it amazing how little my kids remember from when they were 8/9 and younger.
Well done on starting a DD of £1k a month, why dont you aim to increase that by say £100 a month, for 2-3 months, see if you can easily live on the reduced amount? 1000 a month seems a lot just for treats and drinks, meals out etc.