Sabrina Must is wondering where her vacation rental bookings have gone.

“I would have made upwards of $12,000 in a month in the summer,” says Ms. Must, 37, who for just over three years has short-term rented her two-bedroom, one-bathroom property in Encinitas, Calif., a beach town located about 25 miles north of San Diego. “Any weekend I wanted to be booked during the pandemic, I was booked. It was kind of like that prepandemic. Not as busy, but still busy.”