I'm looking for a unit to buy in Melbourne but I don't know that much about the process and want to avoid getting burnt.  

My questions are:  Is it true that I don't have a cooling off period if I sign a contract after I've gone through it with a solicitor?  I definitely don't want to sign anything until a solicitor has gone through it.. is there any way to protect myself?  I would want to organise a building inspection but not unless the seller has agreed my offer.

I'm getting a home loan on the basic that I put down a big deposit.  But I'm worried if the money goes to the vendor in advance of exchange of contracts.  Can I choose to give a smaller deposit until contracts are exchanged?  And what guarantee do I have that the vendor won't pull out of the sale, or disappear, sell to someone else and keep my deposit?

Any advice would be great, thanks