The best way to get a nice score (5000+ if you are lucky) is to fly low, so you can get the Windmills, and try to get all the golden stars and Cranes (you should buy the Crane Booster upgrade). Don't spend fuel unless you really need it. You should buy the next upgrades: Better Model, Aerodynamic, Rudder Control, Fire Engine (leave it on level 1, unless you can't buy anything better than that), Crane Booster, Green Fuel, Hurricane). Those are the most important ones, the other ones are useful too, but these are the most important. Others that may help are Throwing Power, Lucky star, and, of course, the Mystery upgrade (it's a nice thing to spend 3000$, but it is really funny, and can help if you are really lucky). I hope this helped you :).
@OnitsukaTiger_66 That achievement is pretty easy once you know how to do it. Just unlock Middle East (you need to destroy just 1 or 2 towns, and to destroy a town you must kill all the people in it, and destroy the cars if there were). After that, go to Qandahar (you will probably have to complete the challenge in one or two towns in middle east before you are able to attack Qandahar). Then, on the lab, buy 3 bombs, and attack Qandahar. When you see Rambo, just throw all the bombs to him, then you should get the achievement. Good luck!
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