Neighbour's selling

Oh, but I don't even know if I could win the auction from the sale yet.
It's routine to invest in some degree of due diligence prior to securing the property. How do you know what you're willing to pay for the property without knowing how you could use it?

Nobody comes to you and says "here, have some free money, all the work's been done and there are no risks!"
As above you're looking to buy the property to develop, how do you know what to pay at auction when you don't know what can be done with the property. You need to look in reverse, find out what you can and can't do, the value of the properties, then what it will to cost (inc contingency) to get a completed product and work out how muh money you want to make. Then you will come up with what you should pay at auction.