Experts say the president’s border closure proposal would be catastrophic for San Diego businesses that rely on cross-border traffic to fill their registers, shelves, and workforces.

The San Diego Regional Chamber of Commerce told NBC 7 the economic effects of a border closure would be felt locally within the first hour. And after just one day, local businesses could be short more than $5 million.

The chamber's vice president of international business affairs said several businesses on the U.S. side of the border would close completely if the closure lasted just one week.

Not only would customers be forced to make up for the losses in the form of higher prices, they’d also have less help in store aisles, according to Albert Armas, CFO of Selecta International Food Market in Chula Vista.

To go along with a potential 300-percent increase in produce prices, Armas says San Diego businesses would be without the 25 percent of employees who commute from Mexico.

"The customer service end is going to be affected,” Armas said. “It not easy to find a workforce that specifically specializes in Hispanic markets, so that's my concern more than anything else.”

Viviana Nuno likes to shop the best produce for her family, but she’s worried about how expensive her grocery shopping trips could become if the border closes.

"Prices are gonna go up. We're not gonna be able to spend as we used to, so yes, I'm worried,” Nuno said.

Love carne asada and other Hispanic-style cuts of meat? Armas says a border closure would make those items harder to find.

"If they're off the market and we're required to purchase merchandise at a higher price, then obviously, the price will go up,” he said.

Nuno says closing the border is a bad idea, but she thinks President Trump knows what he's doing.

"I think the president is a smart person,” she said. “But I don't think congress will let him shut down the border. I don't think so. I don't think so. I still believe in the constitution of this country."