A tenant in a co-op owns shares of the building corporation and not the actual brick and mortar of a unit. The corporation pays the real estate taxes, which appears as a single property and passes along that cost along with any mortgage payments to the shareholder. In condominiums, each unit owner owns the apartment, fee simple, and therefore each unit is taxed separately. Both the co-op and the condominium have boards, which manage the buildings and pass on the monthly costs of maintaining the common areas and services to the tenants.
In NYC it is common to ask about the financial health of the buildings, how much of the maintenance in the co-op is deductible for real estate taxes, as well as what is required for board approval. Some of the most prestigious co-ops line Park Avenue and Fifth Avenue in NYC. They may not allow financing for purchase and have the right to approve or deny the sale of shares whereas the condominium board does not have the same powers to approve or disapprove the transfer of ownership.
In Palm Beach, the differences between co-ops and condominiums are blurred. Although the form of ownership remains the same, some condominiums have leased land or some coops allow individual owners not to upgrade their windows. I am told Canada even has condominiums on leased land i.e. leasehold condominiums. Therefore it is important for the prospective buyer to understand these differences and consult with a knowledgeable agent.