I think Bugaboo Australia will loose out from this ha ha ha ! When you get $5000 your tempted to buy nicer things! I think looking back I should if bought better quality than I did as if your having more than one baby it does not last. I think you can set baby up second hand for strollers and cots and buy new for mattress and clothes for around $1500 and second hand carrier all from eBay in great condition . If you want the new pram like I did ( mountain buggy) and new stuff you could spend the 5000 very very easily and more. I am on baby number three. Sold all baby stuff and am now buying second hand .... No longer get bonus either as hubby earns right on the limit .
There is a lot of quality items in eBay . Cots are fine if you buy a new mattress and some strollers are amazing .... You will need money for nappies , good idea to put money aside for that .
Once all the basics are bought the nappies and wipes are the expense. I have 3 in nappies and by far that's our greatest expense right now . I I was getting the baby bonus again I'd stash 1000 away to cover nappies and I would buy in bulk.
If you buy well you can resell. A good stroller such as a bugaboo / mountain buggy can last a few kids and will still have a decent resale value.
But all up you can spend as little or as much as you want depending on what you want. Shopping for baby is fun though!!