You have to be ten days on seniority, and under the breeding section on top it says sales right above store click on that.
Breeding tab -> Sales
You must pass the second riding level before you can access the auctions and buy another horse.
You can only take your horse out after you bought it from the auctions or private sales.
Answer You can't bid on your horse. You can only cancel the auction.
You buy it in the auctions or private sales.
You can buy one in the private sales or auctions.
You must buy one from the Private Sales or from the Auctions.
You can buy it from the auctions or you would have to breed two horses.
Go onto auctions and click on the one you want
The only way is to buy in the direct sales or auctions.
It is not possible to change your foundation horse's breed on Howrse. You can however wait until you are able to access the auctions or sales and buy a horse of another breed, or you could breed from your current horse to produce a crossbred.
Buy one off of auctions or get one in a card pack.