An older low-rise building without a recent reserve fund study makes a lender nervous, because an underfunded reserve can mean a special assessment lands on the new owner shortly after possession, and that risk gets priced into how quickly a buyer is willing to commit.
Unit-specific issues add more delay on top of the building-level ones. A dated kitchen, a missing storage locker or a lack of in-suite laundry narrows the buyer pool in a way a single-family home in the same neighbourhood does not experience.
A seller who gets ahead of the reserve fund question and documents recent building maintenance before listing usually sees offers move faster than one who waits for a buyer's lawyer to raise it first. Get your hand-reviewed valuation from Joel Dyck.