The Appraisal Institute of Canada requires its members to remain independent of a transaction's outcome, and an agent who is also the appraiser has a direct financial stake in the number landing high enough to support the deal, which undermines the entire point of an independent opinion of value.
The Law Society of Saskatchewan similarly expects the lawyer closing a sale to act without a competing interest, and that independent legal review is part of the $800 to $1,500 a Saskatchewan closing typically costs in legal fees, a cost worth paying for someone with no stake in the sale price.
Separate professionals checking each other's work is the system working as intended, not an inefficiency to eliminate. Get your hand-reviewed valuation from Joel Dyck.