Since Hinterhalt 3 is no longer accessible, you might enjoy these similar strategy and tactical titles that are often available for free or at a very low cost:

: A grand strategy game that often features heavy discounts on K4G.com and other authorized retailers. Where to Find Legitimate Free Games

: Known for giving away at least one high-quality game for free every week.

: Frequently goes on sale and offers deep strategic gameplay similar to the Command genre Hinterhalt occupied.

: A great source for free and "pay-what-you-want" indie titles. Hinterhalt 3 Price history - SteamDB

: A free-to-play tactical first-person shooter that offers large-scale modern combat.