An interesting problem if there is no hard data available. You may have to solve it using logic.
I have an amenity which would typically would be expected to have a neutral-to-positive appeal.
However, the specific location carries with it consistent hazards (errant slices or hooks).
Logic would argue that the golf course view/proximity is diminished by the bombardment.
So,with this alone, there is a reason to consider a downward/offsetting adjustment for the view/proximity due to the improvements being pelted by golf balls.
Can the hazard be offset by putting up some kind of screen/net? That isn't ideal (who wants that, all other things being equal) but at least it will minimize the damage done to the house.
If the answer is "yes", then there is a basis for a dollar adjustment (along with some modification to the view impairment that the screen may create).
In the big scheme of things, how much of a premium would be associated with the subject's (or, is it Subject's?) location without being an alternative target to the fairway?
Not all conditions/influences can be quantified in the grid. Logic and sound rationale can support an adjustment in lieu of that data. The objective is, after the discussion of the condition, does its impact on value appear reasonable (if the location was worth a 10% premium without the hazards, should it be worth less with the hazard? If less, how much... maybe to the point of offsetting the premium?).
In addition, I'd find brokers/agents who actively sell in the golf community and pose the question to them. They may not be able to supply me with a specific adjustment but then can probably give an indication of the scale of the impact vs. what otherwise would be a positive amenity (proximity to the course and view).
Good luck!
