I realize you are trying to do your "homework", but I honestly think you need to do this on your own.
First, go to the local feed store where you are going to purchase feed and ask them what the feed cost - it varies greatly on brand, location, etc.
Then, go to where you are going to board (keep) this animal and ask them for price. How much for barn space, how much for pasture, utilities, etc.
Then, call the local vet and ask how much is a standard trip charge? Vaccination price?
Then, call whoever is going to trailer the animal to and from places and ask how much they charge per mile.
Then, if you are going to buy insurance, call the company and ask them what the charge is.
Then, check about AI'ing charge or bull rent, (I am assuming this is a long term project), and see what it is going to cost to get her bred.
Then, and only then, if you still decide to buy an animal, call whoever you are going to purchase the animal from, and ask for the price.
Add all the expenses and the work is done. But, it really is up to you to do the leg work.
Good luck.