Oooh kiddicare in Enfield you say.... That could combine well with a Tottenham ikea trip, and the flagship mothercare is there too. Juniper are you nearer Croydon? I am sure there are warehouse sized stores there that might enable you to try out buggies etc.
I have been idly looking on eBay for clothing bundles, as the only things I am likely to get new are a car seat, cot mattress, and ... Um ... That's probably it! First time round, in the first year we bought new a few special outfits, a moses basket, car seat, bjorn, babasling, bumbo, loads of Medela pumping and storing milk kit, the above discussed Bob monster-buggy, travel cot (Asda £20!), cot mattress, baby bedding, but got the cot frame and a set of stairgates from an NCT nearly new sale at £30 each, all the babygros and basic clothes came from friends and that circle is still going (I'm wearing 5th hand maternity clothes!), reusable nappies also handed on by the tribe, a sort of standalone kitchen cupboard/shelf unit on wheels repurposed as a changing table, a Quinny chassis from someone on MN, an umbrella fold buggy from someone at work... We must have saved hundreds. We don't have a big enough house to fit proper nursery furniture, although I pine for the day I can deliberately match things! DS is now in a mid sleeper bed also bought off someone at work, for £45, and baby so far has a new (bought but never used by someone at work) Kari-me sling.
Reusable nappy tip, if anyone's planning on using them: store them ready made up, wrapped with the cover on. We had a nice wicker basket for this, on a shelf of the changing table. Then you can easily grab a few to put in the changing bag, unfold and use just like a disposable when out and about. We have a few drawstring nylon bags, like gym kit bags IYKWIM, which I'd use as 'toxic waste disposal' to get soiled ones home. A soiled reusable nappy fits in a plastic nappy sack, just, and then gets tied and lobbed in the gym bag as a clearly marked laundry receptacle! Rather than cart the great big changing bag everywhere, I got a large toiletry bag, like a man's sponge bag, to use as the 'short trip out' changing bag - you can fit a pack of wipes, three or four disposables, nappy sacks, and a tube of bum cream in there easily. All you need is to find a bin for the toxic waste, and you're sorted.