Hey
Being a IT GUI developer with human computer interaction and usability focus, I just cant look on any GUI and not to get the ideas how to make it better ;) I just thought I'd post some of my thoughts here.
I would suggest to add some basic filtering to the Aircraft Market. I would deem the usable criteria to be aircraft type (as now, but also with ALL option, maybe also with aircraft families like show all B737NG offers), aircraft class (prop/RJ/Narrobody/Widebody), max/min prices for instant buy/credit/leasing and bid prices for buy/credit/leasing, aircraft age, aircraft location (continents and countries), number of seats..
Another thought would be to blend in the basic data of the aircraft directly in the entry, which would simplify the usage especially for beginners.