I would imagine You could talk to the marina especially if you are Interested in keeping the boat there, and work a deal on reduction of the sales price to square up the money owed to the marina.
It’s possible that the marina could have already attached a lien to the boat.
Here is the verbiage from my slip contract.
17. LIENS AND SALE: Paradise Marina shall have a possessory lien against the boat, to secure any rent, additional rent, or any amount due and unpaid under the terms of this Lease or for any other monetary amounts which may be owed by Boat Owner to Paradise Marina. The lien shall attach to the boat and personal property on or about the boat including, but not limited to, furniture, electronic equipment, tackle, appliances and apparel. Paradise Marina shall enforce its lien in compliance with the laws of the State of Maryland.