It is not pure luck.
In addition to Snapshot103's comment:
Platforms are more luckly to be found in equal horizontal intevals.
Got over $10 000 easy on first day
To get 17000 points in 25000$ just buy the superslide and max length plus the H.I.G.H tec glider, sugar rocket, rest fuel. then you can go 16000+ at least.
You can always be one of the first to finish, having little money and living long happy life in the name of motherland...
OR
You can sign under contract, becoming rich and famous champion, no matter the cost... and, possibly becoming slave of...
I used dual machine gun as weapon (damage upgrade, put on back) + basic gun as shield (health upgrade, put in front) at all levels. After i got some money i put damage upgrade towers at free places.
It was very effective.
P.S. Flying shields can be shot with basic gun (shoot in the sky at almost max power).
At the final level you can use this strategy too, if you put mine tower at top position.
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