Justin Aldrich has worked at hotel chain Marriott for more than seven years, and in that time he's learnt a lot about the industry.
In an article in Insider, Justin revealed the one charge hotel guests are bound to moan about.
He said: "We get guests every day who will go to war to stop their credit card from being held for an extra $25 incidental hold, which the hotel needs on file to cover things like charging room service to your tab or paying for any damages you may leave behind."
An incidental hold charge is used by hotels as an insurance policy that covers costs such as damages, room service and trips to the mini bar.
Justin added: "Truthfully, they most likely authorised your card for a little bit extra and didn't explain it to you, but there's no need to get red in the face.
"If you don't leave damages, order a pay-per-view movie, or charge things to your room, the money will be released back to your card in three to five days, I promise."
Another hotel employee echoed Justin's claim too.
Hotel worker Andréa DiBruno explained that hotel guests are always concerned about charges placed on their debit or credit card.
She explained that payment cards are used at the check-in desk to authorise the transaction.
She said: "We'll do a transaction with your card. We will be authorising your payment, not charging. Yes, there is a difference.
"The authorisation is a temporary hold, so stop yelling at us when we ask for your card."
While most holidaymakers will get their hold charge returned to their account, some will be billed for damages or mini-bar beverages.
For example, one hotel guest was shocked to discover that they would be charged £41 just to use the fridge in their room.
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