When I first learned to create websites one of the first clients I had was an antique store in the town's "antique district". (an old neighborhood of old 2 and 3 story buildings which once had shops in the bottom, that the town was considering tearing down due to their age and the neighborhood problems there) Someone came up with the idea of just cleaning everything up and restoring the fronts of the buildings and making an "Antique Mall" out of the area.
I was in that area looking for some antique cooking items and an older lady who owned this one shop started chatting with me. It was dead there that day and she may have sensed I could be some entertainment. When she asked what kind of work I was doing I explained that I created websites. That was the beginnings of a great partnership and friendship. I learned about the antique business from her and the way they purchased estates, or clean-out goods and sorted through the goods to weed out the antique goods, flea market goods, yard sale goods, and discard goods to be given to Goodwill Stores. (these may be used coffee makers, toasters, clothing, shoes, repairable appliances etc)
It was this method of sorting a parcel of goods that I really learned from. Not everything old is really an antique. These items may go into a Flea Market stall to be sold. (for less) things that really aren't Flea Market stall sales items, can go into yard sales. Those left overs can be given to non profits like Goodwill stores and they will give a receipt for the stated value.
I learned that this woman had a sister who had a Flea Market stall and ran that 4 days a week. 2 days of the week she helped her sort parcels she had purchased. Her daughter sold the yard sale stuff on the week ends when she wasn't in school. Her husband would take the discard items to Goodwill in their Van.
In this manner they got the best prices for all the goods and had the right place to sell each kind of goods
in operation. Whatever her husband stated the goods value to Goodwill, they gave him a receipt to give their accountant as a charitable donation to use against their taxes.
Some of us just want to get rid of stuff and we can donate or give it away. Others of us aren't in a financial
posture to do that, however, so we have to get the biggest bang for our goods (in terms of bucks) that we can. So by sorting and selling in the right markets we can generate some money quickly.
If you take something to the wrong kind of sales venue, you'll likely not get much for it with a bunch of eager bidders. If you get the same item in the right market it may sell and fetch a reasonable price. In a yard sale they may figure you are just wanting to get rid of it fast and they can get it for nearly nothing. In a Flea Market Stall they know you are paying a monthly fee and running the stall more like a store and your prices may be a bit elastic but not too much.
So, the lesson I learned is that most people will assume you are running a yard sale and cherry pick the good stuff and move on leaving you with most of the stuff you wanted to sell, leaving you to give it to Goodwill etc. In one of my yard sales I made the mistake of putting a bunch of shirts on a clothes line. I had a low price on them. Sure enough, the first woman came and went down the line hunting for "labels" like Polo,
Tommy Hillfiger, Izod, etc to cherry pick the good stuff and run to the next yard sale. I had a lawnmower in the sale and the same woman came by four or five times through the day until closing. Where I had wanted $50 dollars which was a deal in itself, she offered $10 dollars for it. Often these people are buying this stuff to run off to Pawn Stores where they can pawn it for two to three times as much. Resale shops like to get "labels" with clothing items.
Somethings to think about if you don't have a lot of experience with selling. Selling online is possible if you have he skills. Some places will buy your stuff if you give them a receipt with your name, address, and phone number so they won't appear to have received stolen goods. Then they will sell it on eBay. But you don't have any of the headaches that they will with that kind of selling.