Belarion horses did not have an armor but that is not because he could not afford it but because Belarion did not like his horse being burdened by heavy armor
He needed speed and Belarion himself is confident that he could protect his horse.
But look at the elite guards of the Kan, their horses are equipped with armour.
And in a cold weapon era like this, a heavy armoured horse is like an unstoppable tank.
The rider is full of armours and the horse is also fully armoured.
It is like they are wearing invincibility clothes.
Oen person could kill five people. The stronger one could even kill ten people alone before they have to retreat because of the exhaustion.
Most bale and sword would break after killing a few people and have to be changed.
This is why some people bring two or three sword and a few other weapons in their bags.
But the weapons of the Brolgadhr rarely breaks.