Broker's Price Opinion (BPO)
When a licensed agent, rather than an appraiser, sizes up what a home would sell for, the report is called a broker's price opinion. Lenders use BPOs to price foreclosures and short sales, and BRRRR investors can ask an agent for one to test an after-repair value before buying.
BPOs cost less and come back quicker than appraisals, though they lean on the same recent sales of similar homes. Banks selling real estate owned often set list prices from BPOs, which is one reason those prices can lag the market in either direction.
It is not a substitute for the appraisal at the refinance. The lender will order its own. An agent's opinion is still a useful check on the after-repair value that goes into the calculator, especially from an agent who sells renovated homes in that neighborhood.
Further reading: Broker's Price Opinion (BPO) on Wikipedia.