Owner means a person, firm, corporation, nonprofit organization, partnership, government, guardian, conservator, receiver, trustee, executor,or other judicial officer, or other entity which, alone or with others, owns, holds, or controls the freehold or leasehold title or part of the title to property, with or without actually possessing it. The definition includes a vendee who possesses the title, but does not include a mortgagee or an owner of a reversionary interest under a ground rent lease.