Your buyer wants one because it is the only reliable way to confirm the corporation's finances match what was disclosed during showings. A reserve fund that looks healthy in a listing description can turn out to be underfunded, and the certificate is what actually proves the numbers.
It also protects the buyer from inheriting a problem. If a special assessment of a few thousand dollars is coming due, or if the corporation is behind on fees from a previous owner, the certificate surfaces it before the sale closes rather than after, when it becomes the new owner's bill.
As a seller, getting this document ready early keeps your condo sale on schedule instead of stalling during the buyer's condition period. Get your hand-reviewed valuation from Joel Dyck.