The financial strains on the Secret Service under the Trump administration are now well-known.

And you can add luxury portable restrooms to their mounting bills.

The agency spent thousands of dollars to rent the restrooms during the president's August "working vacation" at his golf club in Bedminster, N.J., according to a review of purchase orders flagged by the progressive PAC American Bridge and verified by USA TODAY.

The agency signed a contract with Imperial Restrooms to provide trailers on Aug. 3. That contract was updated a week later, bringing the total spent on the restrooms to $7,100 from Aug. 3 to Aug. 21.

"Leave it to Donald Trump to find a way to spend thousands of taxpayer dollars on a port-a-potty, " American Bridge spokesperson Brad Bainum said. "This man is literally flushing our money down the toilet."

It's one of many purchases the Secret Service has needed to make in order to protect Trump, who has spent almost every weekend as president at properties he owns on the East Coast, in particular, the Bedminster golf club and Florida's Mar-a-Lago. The agency also spent $13,500 on golf cart rentals for Trump's August trip.

Since the president maintains a semi-regular presence at each resort, these trips are more expensive for the agency than quick pop-ins. The Secret Service is required to pay their own way, even at Trump Organization properties, because the agency is forbidden from accepting funding or resources that have not been appropriated by Congress, including hotel rooms.

The regulations are meant to guard the agency from any possible compromise of its protective mission.

Yet even as the agency spends money on portable toilets and rented golf carts, the Secret Service can no longer pay overtime to hundreds of agents who have already reached federally mandated caps on salary and overtime allowances that were meant to last the entire year, USA TODAY reported earlier this week. On Wednesday, Secret Service Director Randolph "Tex" Alles told his agents that he is "fighting" get more than 1,000 agents compensated for the hundreds of hours of overtime they've worked since Trump took office.

Imperial Restroom is based in Florida and has offices in New Jersey.

"On any given weekend, dozens of Imperial Restroom trailers can be found parked at weddings, sporting events, parades, and countless other events," the company says on its site.

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