Cooperative Apartments [Co-ops]: In a co-op, residents do not own their individual units like in a condo. Instead, they own shares in a corporation that owns the entire building. Each shareholder is granted a proprietary lease, which allows them to occupy a specific unit. Since the corporation retains ownership of the building, any alterations or modifications made to individual units typically require the approval of the co-op board. The alteration agreement, also known as an alteration or renovation application, is a document that outlines the terms and conditions for making changes to the unit. It usually includes details such as the scope of work, insurance requirements, and any associated fees or deposits. The co-op board reviews the proposed alterations to ensure they comply with building regulations and do not negatively impact the overall structure or aesthetics.

Condominiums [Condos]: In a condo, individual residents own their units, and there is a separate legal entity known as the condominium association or homeowners association (HOA) that manages the common areas and shared amenities. While condo owners have more freedom to make alterations compared to co-op shareholders, there are still restrictions and guidelines in place to maintain the overall integrity and safety of the building. Condo owners typically need to seek approval from the condo association or HOA before making significant alterations to their units. The alteration agreement in condos is similar to that of co-ops, outlining the proposed changes, insurance requirements, and any applicable fees or deposits.

In both co-ops and condos, alteration agreements serve to protect the interests of the building community and ensure that any modifications adhere to the building’s rules, safety standards, and aesthetic guidelines. It’s essential for residents of co-ops and condos to understand these agreements and follow the proper procedures when planning alterations to their units.