Board Thread:Questions and Answers/@comment-27859680-20160224140225/@comment-26518423-20160302024857

There will (eventually) be lots of cars that have 400% multipliers, with GEM cars paying even higher returns. I usually buy (for coins) tails and link cars because they can pay over 500%. There are usually 4 of them offered, but they add up. I think "best" is buying any car that will increases your payback. Start with what you can buy today... and buy better cars as they are offered.

If you eventually retire the 400% cars, they'll come in handy later. When special challenges arrive, they provide flags that'll temporarily increase passengers in your station, and you can load up an extra train or two.

I reached level 250 with 4 billion coins banked.