I'm sorry to say but have you looked at the price of rent in Melbourne of late.....$1000. would not cover his first months rent depending on the suburb. We are on the fringe of the burbs on the country side and that amount won't cover the first months rent here so if he was to look closer to the city it would be a lot more.

I think I'd ask him where he thinks he'd like to reside using a km radius and find out costings of rent for that.
Don't forget to add in the bond as well for rentals.
Not to mention the cost of food on top. Sorry to burst your bubble on the amount he'll need but if your not wanting him to bludge off of you he needs to take all this into account.
And a job there are plenty of web site where he can find work before he gets to Melbourne.

Good luck