A BPO and a CMA are similar, in that they each provide an analysis/estimate of the probable sale price of a particular property. Both require a standard disclaimer (the same language that had previously been required for a CMA) that the pricing estimate is not an appraisal and has not been prepared according to the rules that govern appraisals.
The main differences are in the minimum required content of each type of pricing estimate, and the uses for each.
A CMA has no required content beyond the required disclaimer. A BPO requires a minimum of seven additional pieces of information (included in § 455.608f(c)), plus the signatures and license numbers of both the preparing licensee and the broker or a designated associate broker. Though some of these additional items might also be included in a CMA, they’re only required in a BPO.
Further, a CMA must be related to an actual or potential sale/lease transaction, while a BPO can be done in a set of four situations that are not necessarily transaction-related. For clarity, there is also a list of scenarios in which a BPO is not allowed.