Austin, Austin Austin,
One more time - no time adjustments, no extrapolation, and no assumptions.
If the size and other attributes of the property can be bracketed, it can be ranked within the range indicated by the closed, pending and active sales data, with the latter generally exceeding (at least a little) the upper end of a reasonable value range for the subject. The data are what the data are. Present it all and let the trend identify itself. If there is a trend, we observe and report; we don't editorialize on the deeper meaning or search for reasons to discount or ignore a trend just because we don't agree with it. We also don't apply a demonstrated trend from one market segment to another, unlike some of the AVMs currently in use that compare everything in a town or a region by size and age.
Another thing. These trends are not universal, even within our market areas. Different price ranges and neighborhoods have different trends in action at any given time. Even neighborhoods featuring similar sizes, quality and condition levels differ from other areas with comparable but different location influences. It is necessary to approach each appraisal assignment with an open mind and deal with it in accordance to the specifics of that assignment. Indeed, no two are exactly alike. Lucky for us as appraisers, or we'd be out of business pretty quick.
Is there a bubble? I think so, as do you. Is this a stable market and are these gains subject to future reversals? I don't think so, but I recognize that reasonable people might disagree on that one. Are these appreciation trends around here sustainable? I don't think they are; again, same as you. The thing is, it doesn't matter what I think, or what you think, with respect to the causes of these trends or foretelling what the future will bring; the only thing that matters is identifying them and reporting their effect on our appraisals. I try my level best to avoid making adjustments of any type unless I can demonstrate and support them in one way or another, usually by comparison of the data to each other. It's not uncommon for me to make no adjustments in an appraisal except for building area because the data are otherwise that similar. It all depends on the quantity and comparability of the data in the assignment.
You really should pay more attention to Brad's response earlier in this thread. He's the head hot rod at his bank here in SoCal and he reviews residential appraisals all day long. He did the same thing back east prior to this job, if memory serves me correctly. If he's saying that (effectively) nobody is using time adjustments right now, who are you to say that he's stretching the truth just because it contradicts your assumption? These price trends have nothing to do with shoddy appraisal practice. The market does what the market does.
George Hatch