I would not assume lease length is causing the difference yet. It may be travelling with condition, exact location or seller motivation. Compare properties with similar condition and neighbourhood first; otherwise a less appealing unit with a shorter remaining lease can make lease length look...
The one completed transaction gives you firmer evidence than the listings, but it creates another question: is it close enough in layout and features to guide this flat? If it matches the micro-location, floor, outlook, parking and lease position, I would give it substantial weight. If those...
A two-stage approach may keep this manageable. First request only complete responses within the stated bedroom count and target budget. Then compare commute practicality, room layout and condition among that smaller group. Tenure and structural verification still need to happen before any final...