What a bin store is
A bin store sells returned, overstock and shelf-pull merchandise loose in large bins or tables. Instead of pricing each item, the store sets one price for everything in the bins, and that price changes by the day.
Most of the stock comes from pallets bought through liquidation auctions: customer returns and overstock from big online sellers and chain stores. Some bin stores buy truckloads from a single retailer; others mix sources. Many say on their Facebook page which retailers their pallets come from.
Restock day
Once a week the store clears the bins and fills them with new pallets. That is restock day. Many bin stores close the day before restock to sort and fill the bins, which is why so many are closed on Wednesday or Thursday.
Restock day has the full selection at the highest price of the week. Popular stores get a line before opening, and some open early on restock day or sell early-entry passes.
The daily price drop
After restock, the one price for everything drops each day the store is open. A common pattern is something like $10 on restock day, then $8, $6, $4, $2 and $1 on the last day, but every store sets its own ladder. Some stores have a "dollar day" or a fill-a-bag day at the end of the week.
Higher-value items such as electronics and small appliances are often kept on a separate shelf with their own prices, so the bin price applies to what is in the bins, not everything in the store.
Bin stores vs. liquidation stores
Liquidation and overstock stores sell the same kind of merchandise but usually price items individually, often at a percentage off the original price. They restock more steadily instead of once a week. Many stores do both: bins in the middle, priced items on the walls.
Tips
Check the store's Facebook page the night before. Most post restock day, opening time, the price ladder and photos of the new pallets.
Go on restock day for selection and the last day for price. Bring your own bags, wear closed-toe shoes, and test anything electronic before you buy if the store allows it. Most sales are final.