Saskatchewan's rules generally call for at least 24 hours written notice before entry for a reasonable purpose like a showing, and that notice needs to state the date and approximate time, not just a vague heads-up.
Selling with a tenant in place also means the new owner takes over as landlord under the existing lease terms, so a buyer's lawyer will want to see the lease and confirm rent and deposit details as part of a $800 to $1,500 closing file.
Skipping proper notice can create a dispute with the tenant that slows down showings right when you need them to go smoothly. Get your hand-reviewed valuation from Joel Dyck.