this is a VERY objective question. everyone has different income levels, different ideals for what they feel they NEED for their baby. some people are comfortable using second hand furniture, others won't. some will go all out to decorate a "nursery" others won't. some will get by just with a cot and will co sleep, others won't
it's so hard to work out what is going to cost - people tend to "furnish" their needs based on their own income and budget - babies don't need a lot - a lot of it is more for mum and dad's benefit! having said that, some "convenience" products are things some people find a necessity, some would find that same item a waste of money.
i would sit down and work out what is important to YOU to have for your baby. will you breast feed or formula feed, cloth nappies or disposables etc. have a look around and get a rough idea - will you be happy to use second hand furniture etc - if so, scope out ebay for a rough idea on the "going" price for those items. if you can't bring yourself to use second hand, will you go kmart/target furniture or will you want higher end stuff (boori etc)
as i said, it's VERY subjective and will, in a lot of ways, depend on your own requirements. i'm the first to admit we've paid out more for furniture on our baby than we "needed" to - but we also spent a hell of a lot of time, money and emotion getting her, and we decided if we could spend thousands of dollars on treatment, we'd get furniture that worked with the rest of our house (antique/older looking stuff) - we could have used second hand or simple white furniture, but we went with what WE wanted - but it's not for everyone...
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