Selling fast with a tenant in place usually means marketing to buyers who want the tenancy, typically investors, rather than owner occupiers who need to move in themselves. That narrows the buyer pool somewhat but does not stop a sale, and a below market rent locked in is part of what an investor buyer is pricing.
Showings need the tenant's cooperation, since access rules under the Residential Tenancies Act, 2006 require proper notice rather than a landlord's preference, so building in a few extra days for scheduled showings around a tenant's routine is realistic rather than optional.
Assembling the lease, a rent roll and the tenant's payment history before listing avoids the buyer's lawyer asking for them twice, which slows things down more than the tenancy itself does. Get your hand-reviewed valuation from Joel Dyck.