Public stables now sell various kinds of mounts. They're expensive, but that's
intentional. At this time, you can't "rent" at these places.
In addition, some mounts are now fast enough to let you ride away from trouble
if you are ambushed outdoors. (Speed is no help in confined areas) It's not
automatic, but every little bit helps. Only mounts who are "obviously" faster
than normal have this ability. While a mount carrying a heavy load is probably
not so fast, flying mounts can escape from non-flying ambushers a bit more
easily.