If your home purchase sailed through the appraisal and lending process without a hitch, you might not have known (nor cared) that the appraiser sent to appraise the home had first to be approved by the lender.

But if, at the eleventh hour, it was discovered that the appraiser hadn't been previously used by the lender and therefore wasn't yet "approved" to appraise property for the lender, the sale would come to a screeching halt until the appraiser could complete the ream of paperwork for the lender to review (complete with sample appraisals as documentation) in order to be approved.

Just what documentation is required, and why do lenders deem "approval" to be so important? Although requirements will vary by lender and loan type, most approval processes require that appraisers submit a multipage biography along with samplings of their previous appraisal work. These samples should reflect values in the same geographic area as those of the subject property (the real estate the lender will be hiring the appraiser to evaluate.)

It's not unusual, for example, for a lender to require an appraiser to submit sample appraisals of a single-family home, a condo and a multifamily structure (like a duplex). This gives the lender an overview of the quality of work the appraiser does, while also providing the lender with comparables (usually the past six months). The appraiser may need to explain why more current comparable appraisals were not available. The lender's purpose is to become familiar with the quality of work the appraiser has performed and also to learn something about the marketplace the subject property is in.

The lender is not the only one who must approve of the appraiser and his work. The investor purchasing the completed loan must also be satisfied that the appraiser knows his craft and values in the area where the loan is being made. These investors might include major players in the secondary market like Fannie Mae, Freddie Mac and Ginnie Mae.

Whether or not an appraiser is approved with a certain lender is rarely something the buyer need ask. But as more mortgage loans are made by national and regional companies or via the Internet, the process of approving appraisers could become a more common transaction roadblock--one that the lending industry will undoubtedly remedy quickly.