1 bulli in pay, then upkeep. 

Example: Spearman has Spear and Leather Armour. 1 (pay) + 1 (spear upkeep) + 1 (armour upkeep) = 3 per season.

I let you pay your troops in crops, because the troops would likely be more than happy to accept that payment, and because crops have a different value to every player.