I guess it's par for the course, but this game has been very carefully balanced to pretty much require you to spend money if you want to progress to decent equipment and advanced skills and such. The currency you can earn by playing will never buy you any permanent gear, and you'd have to be playing extremely well, and constantly, to keep yourself in 7/14 day rentals of decent kit.
I quite like the game - it's proving to be a great timewaster - but I don't like it anywhere near enough to spend money on it. Thus I will always be at a disadvantage on the battlefield. Ah well, that's the "freemium" model for you!