How to comp and equestrian property with very few around?

[Charlie MacPherson]

I just got the opportunity to meet with a potential seller.  Not highly motivated, but might like a change of pace.

The property is in a high-end town south of Boston.  Close to 10 acres, about 25 stalls, indoor and outdoor riding areas, etc.

Equestrian properties are VERY few and far between.  This town is very high end, with an average sales price for SFRs at $750,000.

To make it even more complicated, there are multiple barns and an outbuilding that's beautifully finished, with a gym and sauna.  Oh, did I mention the guest cottage?  And the inground pool?

It has been listed several times over the last few years and has expired each time.  The seller did give me a hoped-for price, which is less than the previous expired price, so it might be more reasonable.

So, my BP brain trust, any tips on how to run comps on a property like this?  

24 hours from now?