@Smarshian
It’s a civil service job so pretty secure. I know you’re probably right about the credit cards but I just feel better having some emergency funds available.
If the genuine emergency comes up, you can use the card again. In the meantime, it's cheaper to pay the card off with savings because the card will be costing a lot more in interest each month.
As for what to do with the money, I'd save a lot of it in the short term, so you have money available for annual and irregular expenses like insurance, maybe a more expensive holiday than you have now, Christmas, car repairs etc. It doesn't have to go in fixed pots, you just have to prioritise.
So pay debt off, maybe allow yourself an extra £100 pm for days out/meals out etc and then look for a car for DH for maybe around £3k? That should get him a decent one that will last a good few years.
I don't think you have to panic about replacing yours in the short term, 100k is nothing these days, maybe in 2-3 years time?
Buying a car these days seems a false economy as they lose value immediately - in my opinion look at leasing - you pay per month but every 3 years get new one and anything that goes wrong is under warranty, I don’t get why people spend say £10k in a used car any more when for £300pmonth you can get a really nice car
But you'll need to keep paying that £300 pm forever, whereas if you pay £10k for a car, it's yours forever, and will last a lot longer than 3 years - if you borrowed £10k it would take about 3 years to pay back at £300 pm, but after that time, you still have a decent car and no car payments, but with your example, your car disappears unless you keep up payments for a new one or pay probably £5k to the lease company to keep it.