High-end properties should be compared on enduring qualities: location, privacy, construction, design functionality, administration and scarcity.
Location within the location
Orientation, traffic, arrival, neighboring parcels and protected views can create major differences between properties in the same area.
Functional design
Evaluate circulation, ceiling height, storage, service areas, acoustics, natural light and the relationship between indoor and outdoor spaces.
Ownership experience
Review staff, security, maintenance response, rules, reserves and the actual availability of amenities during peak use.