There are a handful of spaces in front of the hotel and then another handful outside the parking structure, but they are open to all visitors and hotel guests, so it's first come first serve.

Not sure how enforced the parking fees at the Sheraton are anyway-- earlier in the year the gates were down and enforced, but entry and exit relied on a complicated QR code and text message system that required use of a smartphone. (Indeed, you could not enter the garage without scanning a QR code every time!) It was rather unwieldy even for me (and I consider myself pretty tech savvy), so I wasn't surprised to see that the next time I stayed there, the system had been taken down. Instead, the only enforcement was the threat that a car not registered with the front desk could be towed.