charge /tʃɑːdʒ/
(v, n) to ask an amount of money for goods or a service
Example: What did they charge for the repairs ?

compile /kəmˈpaɪl/
(v) to produce a book, list, report, etc. by bringing together different items, articles, songs, etc.
Example: The clerk is responsible for compiling the orders at the end of the day

customer /ˈkʌstəmə(r)/
(n) a person or an organization that buys something from a store or business
Example: Let's make sure all invoices sent to customers are kept in alphabetical order

discount /ˈdɪskaʊnt/
(n, v) an amount of money that is taken off the usual cost of something
Example: We are offering a 10 percent discount to all new customers

efficient /ɪˈfɪʃnt/
(adj) doing something well and thoroughly with no waste of time, money, or energy
Example: The accountant was so efficient in processing the customer receipts that she had the job done before lunch

estimate /ˈestɪmeɪt/
(v, n) a statement of how much a piece of work will probably cost
Example: We estimated our losses this year at about five thousand dollars

impose /ɪmˈpəʊz/
(v) to introduce a new law, rule, tax, etc.; to order that a rule, punishment, etc. be used
Example: The company will impose a surcharge for any items returned

mistake /mɪˈsteɪk/
(n) an action or an opinion that is not correct
Example: I made a mistake in adding up your bill and we overcharged you twenty dollars

order /ˈɔːdə(r)/
(n, v) a request to make or supply goods
Example: The customer placed an order for ten new chairs

promptly /ˈprɒmptli/
(adv) without delay
Example: We always reply promptly to customers' letters

rectify /ˈrektɪfaɪ/
(v) to put right something that is wrong
Example: Embarrassed at his behavior, he rectified the situation by writing a letter of apology

terms /tɜːmz/
(n) the conditions that people offer, demand, or accept when they make an agreement, an arrangement, or a contract
Example: The terms of payment were clearly listed at the bottom of the invoice