You can get enough basic stuff to live with for £2k for a couple I reckon- bare minimum basics from Ikea/gumtree. Say £300 for a sofa, £200 for a bed and matress and allow £500 for other stuff- £10 coffee table, basic crockery and saucepan sets, duvet etc- you'd possibly even have a small amount of change left over for a TV.
Then a very basic wardrobe items from discount/low end shops (say 5 tops, 4 bottoms, 2 jumpers, some pants and socks and one pair of shoes) each- say £400 per person for 10 bigger items plus a pack of socks and pants, and you've got over £30 per item. That leaves £100 each for luxuries like make up, hair make up etc.
We took the decision that we wouldn't be looking to replace all out random tat (books/dvds/ornaments/art/jewellery etc). Most of the clutter would lose its meaning/sentimentality if it were replacememts- and these days there's no need to own a lot of it anyway as we go digital.
We were never thinking we'd replace like for like, but we knew we would have enough to manage while we slowly accumulated new clutter with new memories attached.
Our insurance, once we included bikes, laptop and jewellery was coming in at several hundred per year- so over 10 years in which an unlikely even didn't occur we'd have saved way more than we would have spent on the insurance.