We bought very little for dd prior to her being born.
I’ve a lot of baby/childcare experience so fortunately had a fair idea of what was really needed and what would likely be a waste of money although I did still buy a baby bath as I’d used with other babies but we had a big bathroom at the time with a large bathroom sink and so it was really pointless. I also struggled with the sling and never really got on with it, if sling libraries had been around then I would’ve saved myself money there. You don’t tend to use slings with other people’s babies - or at least I never did - so only tend to find out if they’re for you with your own.
We were also extremely lucky to be given loads by friends/family - not all new stuff but we were among last to have the 1st baby and so there were loads of hand me downs which we were not too proud to accept. Baby items are very little used by the time baby is on to next stage/has outgrown so they’re generally in good condition.
The only things we bought new were:
New mattresses for cot and Moses baskets (which we were given)
Travel system inc car seat
Sheets and blankets for cot
Wedge changing mats
Shed loads of Muslins and towels! You can never have too many of these!
Vests and socks - these items don’t last as well as outer clothes, vests get stained and socks get lost! We bought literally a FEW baby Grows and cute outfits and family and close friends bought some lovely items but mostly we were more than happy with the SACKS full of clothes we got given as hand me downs - some of which still had labels on!
One thing we WISHED we had bought and forgot to leading to a very tough night at one point early on? Dummies! Yes I know they’re controversial but I found them an absolute godsend! And I was bf at that point too and they didn’t create an issue there.
Changing tables, nursery furniture, toys,
Breast pump was no good to me as I got no milk out that way but that won’t be true for everyone.
Bouncy chair - bought after she was born and again an absolute godsend and we had a really basic one as there weren’t the fancy rocking/vibrating ones cheaply available back then (almost 20 years ago)
Clothes you definitely want cheap, comfy, wash well items, probably (I’ll get shouted down by the greenies here) that tumble dries too as you do SO much laundry! Oh that reminds me! If you haven’t already get at least one (but a few would be better) of this type of thing (see pic) as very handy for drying small items without having to tumble dry which can mean they get lost or even bugger your machine!
Agree with @Bobbiepin on bottles if you ff at any stage. I bf until dd almost 10 months but it took several (expensive!) trials to find the bottles that worked best for her (and formula! Such a faff!)
Nappy bins I’ve never got along with either. Some of my clients liked them but I found them too faffy and I don’t think they’re really any more hygienic than using nappy sacks (although I’m able to wrap a used nappy with one hand so it doesn’t leak) and emptying bins regularly - a designated normal bin for nappies can be an idea. I just always used bathroom bin - I always have decent sized ones not stupid tiny pedal bin ones though.
Changing bag - again I had the benefit of experience with other people’s babies, I just had a normal rucksack which I kitted out with a folding changing mat, insulated bottle holder once she was ff and med - large ziplock style bags for any wet items! Make sure it has a handle at the top so you can hang it easily in public changing rooms and have it open ready to access what’s needed one handed. Top tip: of an evening sort changing bag for next day as then you’re less likely to forget something essential.
On scratch mits - don’t bother BUT maybe try and get baby grows with them sort of built in - the ends of the sleeves fold over