A cosmetic refresh, paint, flooring, fixtures, tends to take 2 to 4 weeks and pays back faster because it changes how a buyer feels walking through the door without changing the structure. A major renovation, a kitchen gut or a basement finish, ties up months of time you may not have and does not always return what it costs.
Selling as-is is a legitimate strategy too, particularly if you are working against a fixed timeline, but it usually means pricing to account for the work a buyer will factor in anyway, rather than hoping nobody notices.
Joel Dyck's hand-reviewed valuation weighs both paths against real comparable sales before you spend a dollar on renovation. Get your hand-reviewed valuation from Joel Dyck.