Hi Stephen, figures are based singularly, but generally operate in squads unless they’re heavy weapon teams or a lone sniper. Attacks are made from squad to squad, by rolling individually for each figure.
The numbers in the game depend on what kind of miniatures you have available – the forces are randomly generated, but if you don’t have the required miniature you just skip the result and draw again until you get a result that you have a miniature for. Our games had about 20 – 30 infantry on each side, and 5 or so vehicles on the Russian side.
Reinforcements are pretty uncommon – probably only ever 1 in a game, and not all that likely, but could number from 1 to 10 men or 1 to 3 vehicles.
Hope that helps!
Tom Jensen - http://ostfrontpublishing.com/