The Auction Update and Livestock Sale Update are provided weekly as a free service to our readers and advertisers. If you have any questions or would like more information about having your sale listed, please call us at (800) 275-5646. May 14-15 Online Equipment Auction, (303) 589-4119, (970) 215-3440 or www.NiwotAuction.com. May 15 Niwot Auction, Online Only, Longmont, Colo., (303) 589-4119 or www.NiwotAuction.com. Online Only Unreserved Auction, (800) 937-3558 or www.BigIron.com. Construction & Contracting Equipment, Henderson, Colo., (866) 515-1668 or www.RollerAuction.com. Inventory Hotlist Internet Auction, (866) 608-9283 or www.PurpleWave.com. May 16 Arbortanics Trees & Shrubs Internet Only Auction, Littleton, Colo., (866) 515-1668 or www.RollerAuction.com. Love Your Gutters Internet Only Auction, Denver, Colo., (866) 515-1668 or www.RollerAuction.com. Colorado Equipment Internet Auction, (866) 608-9283 or www.PurpleWave.com. May 17 Household Consignment Auction, Wellington, Colo., (970) 568-9828. Weekly Consignment Auction, Greeley, Colo., (970) 356-2998. May 18 Schmidt RE Auction, Pierce, Colo., (970) 356-3943 or