There are three sources of income in Blitzkrieg. The first is the command centre. Your command centre represents the high command of your nation and as such recieves an income based on the availible military budget. This income can be boosted during the course of the war. The Axis and Soviets can shift their economy to a total war setting, greatly boosting the income their command centre generates. Soviet players should also request Lend-Lease shipments as soon as possible because these will deliver both payment in kind (military equipment) and hard currency. The Allies do not get a total war bonus, but when the US intervenes in the war the huge American economy will greatly boost the Allies income, allowing them to afford the expensive high-grade equipment favoured by their military leaders.
The basic income from the command centre can be supplimented by siezing land. Rather than every building granting cash, the system now revolves around the capture of key buildings. These are marked on the preview map before the game starts by a $ sign and in-game by a flag. Finally, the health bar of these buildings will be green while the health bar of inactive buildings will be blue. While these buildings grant a supplimental income it is still possible to use the other income streams to offset major territorial losses. A very able general can bounce back even from huge territorial losses and so in Blitzkrieg a loss of land is never a reason to throw in the towel. The game is not decided by who can grab more land in the first few minutes but by who is the better general overall - indeed the different factions vary in how well they can sieze land, and it is to be expected that the Axis with their paratroopers and excellent mechanised infantry will dominate the map in the early game. Simply biding time will allow for T-34s or US deliveries to come online and the situation will be reversed with careful planning and well-executed counter-offensives.
The final way to generate an income is from battles. While the huge explosions in game may suggest otherwise, battlefields in reality have much salvageable equipment. Success on the battlefield means the ability to tow away damaged and broken chassis for repair or convertion into self-propelled guns such as the famous StuG III. To simplify this, every kill in Blitz will simply grant 15% of the value of any enemy unit killed back as a bounty.