Simply defined, a co-op is a multi-unit apartment-style building where each resident holds shares in the co-op corporation, with a contractual right to occupy a particular unit. The resident does not hold title to the unit. There is a board of residents who oversee the maintenance and the annual budget. Potential residents are pre-screened by the co-op board and are generally asked to participate in an interview.
Most co-ops have additional rules: Most disallow rentals. Some have strict pet rules. Many have rental parking.
Since you own shares in a co-op, obtaining financing is not easy. There is a select number of financial institutions who will loan for top-drawer co-ops.
In a co-ownerships building, the buyer owns a percentage interest in the building and land, and has the right to occupy his specific unit through a registered co-ownership agreement.
As in a co-op, the co-ownership resident is a member of the co-ownership corporation, and there are just a few financial institutions who will finance a purchase in a co-ownership building.
In a condominium, each unit is separately owned and unit owners share ownership of common areas, such as hallways, laundry rooms, exercise rooms, etc. Owners pay a monthly maintenance fee for common element expenses, building insurance, the reserve fund and other amenities. A property management company oversees the annual budget and maintenance.
In a condo, since you own title to your unit, it is easy to obtain bank financing.