Peter Fulmer runs his own real estate appraisal company in Edmond, Okla. Until fairly recently, the features and amenities in most of the homes he appraised were relatively familiar-pools, outbuildings, marble countertops, and pea gravel driveways. This made comparative analysis a fairly straightforward proposition. However, over the last few years he's been confronted by subtle yet significant challenges in accurately determining a home's worth. They center on home technology.

A recent appraisal Fulmer handled underscores this new wrinkle. Here's the scenario:

A 5,000-square-foot home going up in a neighborhood with similarly sized homes has structured wiring, a dedicated home theater with in-wall speakers, a whole-house audio system and Internet-connected home automation. The nearby homes that he'll use as comps to compare values based on recent sales have standard twisted-pair copper wiring and perhaps some retrofitted home theaters. The challenge: How much more do the integrated technology systems add to the appraised value of the new home? Or do they even add any at all?

As digital homes rise in popularity, many builders and new home buyers trust in their minds that technology amenities add value. But ultimately it's appraiser like Fulmer who have a lot to say about that. And even they don't always know the answers.

"It's hard to know, and there are few or no standards in the market to help us make those determinations easily," says Fulmer, a tech-savvy 30-something. "I understand the costs associated with putting the technology into the house because I'm familiar with the technologies being used. But that's not enough - you have to try to determine the actual value of the overall house to someone for whom these technological amenities may not mean much. This is an issue that's going to become bigger and bigger as technology gets used more and more to differentiate homes."

Increased Scrutiny

In the wake of a decade of easy-money lending practices and drive-by mortgage appraisals, lenders' underwriters-who may or may not know what whole-house audio is-are intensifying the scrutiny to which they subject valuations. That makes it difficult for the appraiser who report to them validate and defend valuations of home features that may have few reference points in a given neighborhood.