I agree with all the previous suggestions.
just want to put in another bid for one or more babywearing options (my personal fave was a Mei Tai) this for me was the absolute essential.
Also a big exercise ball for bouncing the baby to sleep on. Worked like a charm for my DD who required LOTS of walking, bouncing and rocking.
If you are a car-free family (Like we are) a light weight stroller that can fold up and be carried on public transport (ours is a Mclaren Volo, got it as a gift). You won't need this until the baby is older, but at some point you're going to stop baby wearing and start using a stroller (for us it was after a year). Also a good quality folding stroller will last a long time. My DD is turning 3 in a month and we use it regularly.
Not essential but really great for winter babies is a babywearing coat. Checkout the babywearing forum or www.thebabywearer.com
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