Another easy way out of needing to label items is to have designated priced tables; almost dollar store style. As much as having "departments" at your sale can be important, or at least helpful, the "dollar store" set up will override this layout. Each table would be set up to represent a dollar amount. Since it's a yard sale, it could be a good idea to begin with the "cents" increments. A $0.25 table, a $0.50 table, a $1.00 table, maybe a $3.00 table, a $5.00, & depending on how high items could go for, even a $10.00 table. It could also be an idea to split a table if there aren't as many items which apply to a dollar figure; maybe have a table that has $3.00 items on the left-hand side & $5.00 items on the right-hand side. For these tables, taking a paint stirrer or something similar & affixing either a simple sheet of paper, stock paper, poster or foam board by way of gluing or stapling it after using a marker to write the prices on, or printing them off a computer in a large, legible font can be a great way to prominently showcase your prices adequately for each section of items.
A little more complicated, yet thorough way to price items is to use these. One of these stickers labeling each item clearly indicates how much the host expects, or anticipates, for an item. If an item can be destroyed or altered by a sticker label, such as a sweater (where the threads could be pulled or snagged), or a picture frame (where an unlimited supply of Goo Gone would be needed), or plastic wrapping that would leave a spot or get pulled & distorted, then attaching one of these, or these could be a viable alternative solution, though more time consuming to affix.
Utilizing these options makes for a more likely chance of selling more items, in so that those patrons who don't prefer to barter, or really want to add up their costs as they walk about your tables will feel more comfortable doing so. Creating the best likelihood that someone who might live a block or two away will leave contented & go back to their house, be unloading their car, their neighbor will see them, ask where they were, where they found all their new things, & they'll share with their neighbor about their experience and it'll be a positive one. Then their neighbor will find themselves thinking that maybe a quick trip a few blocks away seems like a really good idea. Especially since your layout was so good that when the neighbor asked if you'd had much left after, the response they received was "yes".
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