Americans will spend a record $100 billion on summer vacations this year -- 20% more than they spent last year, according to a recent report from Allianz Global Assistance USA.

A portion of those funds will pay for travel-related taxes like taxes on car rentals and hotel rooms -- taxes vacationers might not have budgeted for...but vacationers may also be able to save on taxes.

Related: Want to travel in luxury like Warren Buffett? Here's how...

For example, they can write off part of their vacation spending if they they conduct some business during their time away. "You can't just go away on a luxury vacation and write the whole thing off. There has to be a business purpose," explains David Selig of Selig & Associates, an accounting firm, and TrueTaxHelp.com. "But your husband [or wife] and your children will have to pay full freight."

Parents of children attending summer daycamp can also save on taxes by taking a tax credit for child care. Sleepaway camp is not eligible.

For those taking staycations -- not traveling anywhere but staying home -- and gathering items to donate to charity, Selig has some more advice. "Keep good records. Make sure you donate to a qualified organization and they memorialize your contribution in writing. That's very important. The days of just saying i contributed X amount of dollars, they're gone."

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