Advice on buying at Auction

[Raeanna Argyle]

So after 2 months of looking my next investment property (rental) with no luck I have come across a house I would love.  A duplex! But it's an Auction. This is my first time highly considering buying a house at Auction. Any advice from anyone out there who has done it before would be greatly appreciated. I believe there is a deposit to register. Do I get that back. If I get the house do they keep it? Are they free and clear houses?