Bummer on the land improvements. Would have been nice to have some of this dough for some comforts for crew members, mtx group, and passengers.
If it isn't too late, try and get some offices included. Adds value long term to the structure and less costly if done up front. Obviously reception area nice for passengers who may be waiting for others.
Make sure the hangar floor is painted by a pro who knows what he is doing. Bubbles and peeling will be with you for a long time. May cost a little more upfront...but well worth it.
Normally the original owner isn't the user 15 to 20 years later and the hangar architect should consider this. Very saleable asset down the road if done right.
Make sure the lease agreement addresses what happens if you sell the airplanes or need to relocate. The land improvements are stiff and the airport authority is benefiting greatly. If someone else builds a hangar nearby, will they benefit from these improvements...if so...you agreement should ask for some recovery.
You need an attorney that has worked with airports before to take everything into account. It isn't your typical real estate lease. If the owner has juice in town, find an attorney who knows their way around the airport bureaucracy.
Things can go smoothly with a lot of advance planning and if the lawyer, architect, and general contractor have experince buildign hangars. You don't want to be a test case for the general contractor under any circumstance as the engineering and steel work can be tricky.
