I was given sleeping bags, but have never used them,. We had a short winter this year & I found that wrapping her in a muslin wrap, with another blanket over the top has been plenty. She is 8 weeks now & I still wrap her to go to sleep, (although she generally pulls her arms out now) and I put another light bunny rug over her & tuck it in quite tightly at the sides & bottom. We sleep with the ceiling fan on & it's not too warm yet for two light wraps.

Clothing... I agree with Tenar... I think it's better to have mostly mid-size clothing such as 000 - if you have a small baby they will grow into it, but they don't shrink if you buy too small clothing!
I also waited until she was born to take the tags off everything we had bought & been given, DH had instructions on how to wash everything while we were in hospital.
Keep in mind too your baby is due in summer, he or she probably won't want much more than a singlet & nappy a lot of the time.

HTH