In the era of low-altitude economy, drone medical transportation provides critical time guarantee for emergency treatment and organ transplantation. However, in Hong Kong, one of the cities with the highest building density in the world (average plot ratio of 8.5), its large-scale application faces three contradictions: airspace conflicts caused by the lack of flight safety standards between buildings, controversial demands of the community for rooftop space ownership, and institutional vacuum of cross-building property coordination. This study breaks through the traditional property rights paradigm, proposes the concept of "low-altitude airspace building rights", establishes a "three-dimensional property rights" analysis framework (surface rights/surface rights/airspace rights), and reveals the "vertical fairness" problem of airspace resource allocation in high-density cities. Through the Q method, the value orientation of multiple subjects such as government, property managers, medical institutions and community residents is analyzed, and three typical positions of "life priority", "equity balance" and "technology suspicion" are identified, deconstructing the core contradiction of the dispute over the boundary of rooftop space rights and responsibilities. This study finally proposes the "shareable airspace plot ratio" indicator, incorporates parameters such as drone channel width and height layer interval into the statutory building planning system; designs a "honeycomb property rights allocation model" to achieve hierarchical confirmation of building facade space through contract governance. Keywords: low-altitude airspace construction rights; three-dimensional property rights; Q method; honeycomb model; Hong Kong co-construction management