Slang

a rip-off: an item that is unreasonably expensive
pay through the nose: pay too much for an item
fly-by-night: an untrustworthy business that might close quickly
buck: dollar
sucker: a person who is easily tricked into doing something
take someone to the cleaners: get someone to spend a lot of money unnecessarily
pick up: get
be on sale: available for purchase at a lower price
on a first-come, first-served basis: not reserving an item for sale
green: naive or a novice at something, without experience
gimmick: a clever sales trick to get people to buy
have someone's number: to know something about someone
cough up: give unwillingly
wad: a think pile or mass of something, like money or chewing gum
pay an arm and a leg: spend a great deal of money
slash prices: cut or reduce drastically
blow money: spend money carelessly