Sell is a verb. So you don’t “price things for quick sell”, you price them for quick sale. It’s not a clearance sell. She sells sea shells all day long. The grouper offered her ten clams in exchange for the abalone soap dish. She wanted to sell it, so she accepted.
Sale is a noun. A sale is the total purchase, individually (She made a big sale of 27 sea urchins to one tourist) or as a group (She made a lot of sales at her sea shell booth.)
Sometimes, you don’t want to sell something, like Neptune’s trident that he’s loaned you to display your pearl necklaces on, so you mark it NFS, or Not for Sale.
I think where the confusion comes is
is that sale is also a specific event (remember, it’s a NOUN)… a price reduction that a shopkeeper sets up so she will sell more. Having a 50% -off sale always sells more shells, but it eliminates almost all profit so I shall not do it often. Things that are on sale are for sale. You sell things that are on sale or that are for sale.
And if you’re selling sea shells, you’re a resale shop (after all, what are sea shells but used clothing or houses? You resell gently-used good mermaid’s purses (yes there’s such a thing) and hope that you make good sales in that department, or you’ll have to have a sale on them.
Yes, it matters which you use. If you want to be understood. If you want to be seen as professional. If you don’t want to burst your shop’s image bubble.
Auntie Kate The Resale Expert 
Thank you, thank you! Now if only you could do posts on you’re/your, they’re/there/their, lose/loose, etc. the world would be a much happier place 🙂
You have NO idea how much I love you right now for this post… This is probably my BIGGEST pet peeve in the WORLD… in fact, it’s listed as such on my personal myspace and facebook pages! I cannot STAND people who mix the words Sell and Sale up… it drives me crazy!