What is the difference between a sale by private treaty to a sale by auction?

A sale by private treaty is no different to asking for and accepting private offers to purchase the property. It is a common form of sale where any potential buyers can make offers to you at any time, you can consider each as they are made and determine if you have obtained the best offer. If you accepted an offer under private treaty and have followed through to sign the contract, you will not be able to easily walk away from the contract once it is fully formed. If you have allowed the buyer to negotiate conditional clauses into the contract (e.g.: conditional on finance), only the buyer would be able to walk away from the contract on those conditional clauses unless they do not give notice in time under those clauses. You will be limited to your rights to exit the contract once it is signed. 

A sale by auction is another common method of selling a property, where your agent will advertise to as many potential buyers as possible and ask that they attend the auction to bid for the property. The property will be sold to the highest bidder at the auction, if their bid is higher than the reserve price that you have set. When determining whether to sell your property by private offer or by auction, you will have to consider the market trend and the general interest in your area. If there are many interested buyers in the area, then it may be advantageous to opt for sale by auction. You should discuss with your real estate agent for further advice.