How can I get my appraiser to use a FSBO sale as a comparable sale?

The best way to encourage the use of a FSBO closed sale as a comp is to make it convenient for them to confirm the terms of sale. The appraiser will need to confirm if the deed transfer you have found is truly an "Arm's Length Sale".

Simply providing a transfer public record (without having anything else to back it up) will probably not result in it's use in the report. A good appraiser will strive to obtain both transactional data and property characteristic information for any potential comparable sale. Transactional data refers to the details of the terms of the sale. Property characteristic data includes other important salient details about the physical characteristics of the home such as the current condition, renovation levels, accurate living area, etc. Both transactional data and property characteristic confirmed information is required for a comparable sale to be considered reliable.

In the vast majority of areas in Palm Beach County, the MLS is an excellent way for appraisers to confirm potential comparable sales. Examples of terms of sale that are available in MLS include whether the home was purchased with cash or financed, whether there were seller concessions, whether the sale was an arm's length transaction, how long it was on the market, etc. The MLS also will also typically have photos, the contact phone numbers for the listing agent and selling agent, and comments about the home. It is a very convenient and familiar way for appraisers to research.

Although our appraisers would research a public record sale that was pointed out to us by a seller, many appraisers are not going to take the time necessary to obtain the detail needed to ensure it is a “reliable market indicator” (a good comp). In the past we have seen situations where a sale included a trade involving additional property (a condo flat in France, boats, furnishings, etc). We have seen appraisal reports that utilized a public record sale, which we eventually discovered was from one family member to another (not arm's length) despite the two parties having different last names.

Given the time constraints of the appraisal process, it can be very helpful if you can take the time to track down good contact information from the buyer or seller before the day that the appraiser visits the house. Did you know the seller? Do you have their phone number or email already? As an appraiser, I can knock on a door for several days trying to catch the owner at home. However, at some point, the report needs to be handed in and we run out of time. If you or your seller often live in the neighborhood and can simply stop by and knock on the door randomly a few times, it can take comparatively little effort and has a higher chance of success.
If it is a critical comparable that you really want it to be used in the report, you can also try to obtain a copy of the contract that was used or closing documentation. If you have an email address for one of the parties involved you can try to have them send you any salient details about the transaction, the property, the renovation level, and any special circumstances. An email printed out and handed to the appraiser will carry more weight than giving them a phone number and hearsay.

Appraiser's will typically consider a non-MLS listed sale, but only if the sale terms can be confirmed. By following the advice above, you should be able to greatly increase the chances of the sale you found being used by the appraiser.