The owner Snak gra-Bura is not supposed to sell you horses because of her affinity for
eating them. The only way she can sell you horses is if you have installed the horse armor
download , and if you are on PS3 i believe that cannot be done.

Perhaps you misread. If you originally stole the white horse and then explored the
imperial city it might wait for you outside the city but still considered stolen so when
you get on the horse the guards are alerted.

The chestnut handy stables do offer lodging for other horses (except yours) which explains
why they'd have white horses stabled there.

A nice workaround for that is to raise the gate guard's disposition to as high as you can
(bribing works nice) and when you are caught stealing instead of going to jail or having
to pay your fine , the guard who is your friend will pay it for you. This only works for
small fines such as stealing and assault , but not murder.