An auction is a great way to move a lot of stuff in a big hurry. Here is my experience with an auction in S.E. MN. The auctioneer charged 15% for household stuff, so we didn't put any of that on the auction. I can see his point, it takes a long time to auction a $50 dresser. Takes about the same time to auction a pickup, so he makes a lot more per hour. All the farm stuff and vehicles were about half the commision rate. The auctioneer said his team would help organize the items for the auction. In reality they were helpless and disorganized, and my family did most of the work. One of the best things we came up with was to get a bunch of pallets. the week before the auction we worked to clean things up and put everything on the pallets on the floor of the shed. Then on auction day we simply moved the pallets out with the skid loader and fork tines. Arranging the pallets along the driveway, everything was displayed nicely. If the auction co. had had anything to do with it, all the stuff would have set out in three days of rain before the auction. Another thing: List as much of the high value stuff as possible on the auction bill and website. The more that is listed, the more people will be there, and the more money stuff will bring due to competition.
Clean everything as much as possible, make it look shiney, show off the paint, get off the grease, pressure wash if needed. Make sure all the batteries are charged so stuff starts right up when it is time to demo it. Fix tires, pump tires, line stuff up in groups of like-function. Make sets of wrenches and sockets instead of trays of mixed tools. Trays of mixed stuff sells for a buck, or less. Make sure you have the most qualified person following the auction crowd to do the engine starting, or to answer questions. It definitely helps make it look like you are honest, organized, and have nothing to hide.
Clean up the yard and stuff, close up sheds and lock them if they are not part of the sale, remove anyhting shoddy beforehand. It all adds to the image of neat, clean, people selling good quality items.
All that said, it is necessary to have a minimum amount of stuff to make an auction feasible. There is that huge consignment auction on 52 just south of P.I. twice a year, if you don't have enough stuff for your own. It will cost more commision at that deal, I think 15% if memory serves. But it still could net more money than if you have very little stuff and don't get enough people.
Weather won't matter. Rainy days the whole family will come since there's nothing better to do. Saturdays are best of course. Springtime is best too, with people getting ready to do outside jobs, if you have tractor stuff.
Tell the auctioneer to arrange for a food wagon, and advertise it. For some people its the closest they get to a vacation.
Think ahead about parking. There could be 500 cars and trucks parking within a mile of your house. Where will they park?
Get the owners manuals all lined up in big ziplocks and carry them around, and make it real obvious as you hand them out to each buyer as each item sells. They will get the idea that you are erally on top of stuff. Include maintenance records, and talk loud when you tell them what they are getting. Understand the concept?
Make sure you have all the vehicle and trailer titles lined up. You need them in order that very day. Detail clean the vehicles you are selling. People look things over very closely if they are interested in them. They do not have much time to do it, but they do it as a "pack" and if someone finds something out of order, they all get the message.
Care to show and tell us what you all might have for sale?