What changes the calculation is that a lender can be satisfied while the buyer is still overpaying. Completed comparables, the unit’s condition, fixtures and likely repairs help answer what it is worth to you; the valuation mainly affects how much the lender may support.
The two consequences...
I wouldn’t automatically treat vacancy as the cause of the outliers. A vacant home may simply reveal seller motivation—or poor condition—more clearly. Financing delays and a surge of new listings could also change the picture without appearing in completed deals yet. Keep the online sample, but...