A good acoustic will start at around $200 new. You can get a decent electric, with a small practice amp, for less than that. Since your budget is around $500, you can get a nice guitar of either type.
But really, it's about what you like to play. I started with acoustic, then bought an electric. But I found that I'm a better strummer than a picker, and for those big open chords, the acoustic is better. I started playing at age 45, which isn't the best time to learn something that involves fine-motor skills. Strumming rhythm guitar is easier for me because it involves fewer finger movements - just change chords once per measure, as opposed to playing 4-8 notes per measure. It also requires less precision with my right hand, because I'm strumming several strings at once instead of just one at a time.
I ended up giving the electric to my son. He also got my Ibanez acoustic when I bought the Seagull S6.