Jon’s suggestion to start with a larger bike is not necessarily bad, but I will point out two things:
1) beginner bikes that are bought used typically retain their resale value fairly well. So if you choose to upgrade in a year or so, you shouldn’t be out too much. Around here, you can find recent models (last 3-4 years) for between 3K and 4K.
2) I did start with an S40. While it has a larger engine, it is lighter and has less power than the Vulcan 500 due to being a single cylinder. That said, it is still alot of bike and learning to ride it has been a challenge. I don’t know that I would get it as my first bike if I was to do it over again.
Whatever bike you get, you need to take the time to learn how to ride it correctly. With larger bikes, it is especially important that you learn where the friction zone is and how to use it.
In the end, after you take the MSF class and sit on some bikes, you will have a better understanding of what you are comfortable with, both risk wise and ergonomically.