A condo owner often holds a contract for equipment that sits outside the unit, or misses equipment that sits inside it. Before you size anything, sort what you own from what the association owns, because the building documents usually draw that line in a different place than the floor plan does.
Sort the unit from the building
Read the declaration, the bylaws, and any rules the association has adopted. These documents often say which parts are common property and which belong to the individual owner. Shared boilers, building water risers, common elevators, and parking structures are commonly treated as association items. Fixtures and appliances inside the unit boundary may be treated as yours, but the exact boundary varies by building, so do not assume it.
Make your own list
Write down every appliance and system inside the unit boundary, including items you bought and items that came with the sale. Next to each one, note who the documents say maintains it. A list built from the documents will size a contract more accurately than a list built from a walk through the rooms.
Ask the seller before you sign
Ask which items the contract names, whether any building-wide equipment appears on its schedule, and whether the contract expects a particular occupancy or residence condition that a condo association also sets. Ask whether the association already has its own service arrangement, and whether that arrangement overlaps with the items you plan to cover.
Compare the two lists
Lay your unit list beside the contract schedule. Every item you own should appear once. Every item the association carries should be absent from your contract unless the schedule explains why it is there. Where the two lists disagree, the association documents and the contract wording decide the question, not the sales sheet.
This guide does not restate any state's rules for condominium ownership or service contracts. The state pages on this site name the regulator and the statute for each state and say whether that state publishes a roster. Check those tables for the published figures rather than relying on this page for them.