Not sure where you are located, General, or your size. But if you’re really looking for a small, inexpensive bike for back road rides or low speed commutes, and your inseam is not more than 30-32″, I’d recommend a used Rebel 250.
Lightweight, low seat height, 75+ mpg, and there’s at least a dozen of them on my local Craigslist for under $2,000.
If you have little or no experience, I DO NOT recommend a 750 or larger as your starter bike, especially in a sport bike design. If you’re really set on a sport bike style, I’d recommend either the 250 or the 500 Ninja.