The reserve price is a minimum price (confidential) set before the sale by the auction house and the seller of the object. A lot cannot be sold below the reserve price. In France, since the law of 10 July 2000, the reserve price cannot be higher than the low estimate that the public are given.
The estimate, generally between two figures called the 'low estimate' and the 'high estimate', is the estimated value of an object offered for sale by an auction house.
The starting price is the amount suggested by the auctioneer to open the bidding. This price can be lower or equal to the low estimate.