How much is this horse worth?

I'd say between $2500 and $4500 depending on where you are located and where you bought her. Some areas have higher prices (like the Northeast US) and some places bring a better price (like Horsetopia ads VS. Craigslist). It would really depend on actually seeing her action while performing and disposition. Some buyers may be willing to pay more for a horse with those exact traits while others wouldn't pay so much. If you love her and are happy then you got a good deal. :D