DORAL, Fla. — Pablo Sandoval pulled up to a custom car shop here on a recent Friday afternoon hoping to do some business. He wanted to trade in the Porsche Panamera he was driving, order new sets of rims for his two Range Rovers, pick up the gray one that was being worked on and discuss the next car he would buy — a 2016 Rolls-Royce Ghost.

Sandoval strolled inside and, seeing that no one was behind the front desk, leaned on the counter and playfully smacked the bell several times, announcing his arrival. The owner, a Miami native named Alex Vega, suddenly emerged, smiling, with a phone pinned to his ear. Vega hugged Sandoval, kissed Sandoval’s girlfriend, Yulimar Martins, on the cheek and invited them back to his office to talk.

“Spring training is when business gets the craziest because everybody wants to show up with something new,” Vega said. “I’m already getting calls. I’m already preparing cars.”

For numerous baseball players, visiting Vega appears to be an annual off-season pilgrimage. Vega owns the Auto Firm, a garage that customizes cars and sits about 17 miles from Miami’s South Beach strip. Vega helps players acquire luxury cars that cost as much as a small home and claims to have more than 300 baseball clients, from the game’s wealthiest stars to little-known minor leaguers.