So, if you've gotten your garage up to 10, you've got several discounts waiting for you... And the Tier II-VII will all NET you credits on use (buying tank for 60-100% off, then selling back immediately for 50% of full price). So, what's a credit-grubbing player to do? Consult the following guide, where I'll spend way to much time on figuring out how to net ~1 million credits (guessing) for free.
Tier II - H35 - 2.1k
Runners up at 1.5k - Strv m/38, VAE Type B, Chi-Ni, LT vz. 35, FCM 36, L