Those companies typically place a hold on the customer's credit card at the beginning of the transaction for the estimated total, plus a percentage or a fixed cash amount (such as the estimated rental charges, plus 15% or $250 — a policy many customers do not know).
https://en.wikipedia.org/wiki/Authorization_hold
How long should restaurants keep signed credit card receipts? We had a restaurant that was using a manual method of taking orders and completing transactions. We would collect the written receipt, register tape of the calculations and the signed credit card receipt that was signed.
http://www.restaurantbusinessonline.com/operations/advice-guy/how-long-should-restaurants-keep-signed-credit-card-receipts
1 How Long Do You Have to Keep Company Records?  Customers have as long as 18 months to dispute charges on their credit card bill. If you do not keep the credit card receipts from sales transactions, your business could be forced to return the money for the purchase to the customer's credit card company. If the credit card company sides with the customer and you do not have the receipt to validate the purchase, the company can debit your merchant account for a chargeback.
http://smallbusiness.chron.com/long-should-business-keep-credit-card-receipts-58801.html
In the case of debit cards, authorization holds can fall off the account, thus rendering the balance available again, anywhere from 1 to 8 business days after the transaction date depending on the bank's policy. In the case of credit cards, holds may last as long as 30 days, depending on the issuing bank. Signature-based (non-PIN-based) credit and debit card transactions are a two-step process, consisting of an authorization and a settlement.
https://en.wikipedia.org/wiki/Authorization_hold
If you want to release a hold early, or believe that there is an unauthorized hold on your account, have the merchant contact the prepaid card company. The merchant must then send a letterhead fax of the purchase including the following information: 1  Customer name.  Card number.
https://www.accountnow.com/content/why-is-there-a-hold-on-my-debit-card/
Since prepaid cards are not credit cards, you must have sufficient funds in your card account in order to make a purchase. Unless you specify the exact dollar amount of your gasoline purchase, a hold may be placed on your account (up to $125) to ensure that you have sufficient funds for the gas.
https://www.accountnow.com/content/why-is-there-a-hold-on-my-debit-card/
The Internal Revenue Service recommends that you keep any documentation of deductions and income for at least three years. Keeping credit card receipts is not mandatory as long as you have other documentation of the sale such as your deposit records from your merchant account or your cash register receipts.
http://smallbusiness.chron.com/long-should-business-keep-credit-card-receipts-58801.html
For example, if an individual has a credit limit of $100 and uses a credit card to make a purchase at a retail store for $30, then the available credit will immediately decrease to $70 because the merchant has obtained an authorization from the individual's bank by swiping the card through its credit card terminal.
https://en.wikipedia.org/wiki/Authorization_hold
Using your debit card to reserve a hotel – Call ahead. When using a debit card to pay for a hotel room, it is not uncommon for a hold to be placed on the card. When you check in, a hold may be placed on your card account up to an additional 20% of the room amount. For example, if you pay $100 for a room, up to $120 could be held on your account.
https://www.accountnow.com/content/why-is-there-a-hold-on-my-debit-card/
Jonathan Deutsch, Ph.D. on May 13, 2014 Email. Question: We had a restaurant that was using a manual method of taking orders and completing transactions. We would collect the written receipt, register tape of the calculations and the signed credit card receipt that was signed. Because these receipts are used in calculating Payroll for servers I am confused on how long should a restaurant keep (store) signed credit card (merchant copy) receipts? BOE says 3 years, IRS says 3 years, State of CA says 4 but in some articles I have read 5-7 years. What do you recommend?
http://www.restaurantbusinessonline.com/operations/advice-guy/how-long-should-restaurants-keep-signed-credit-card-receipts
how long does a merchant need to hold on to credit card receipts
A merchant needs 18 months to hold on to credit card receipts . A merchant need to hold on to credit card receipts for 18 months long. A merchant needs to hold credit card receipts for 18 months.