Cheap 9mm was 3 yrs ago, I have not checked last few months.
Are you talking a slide mount Red dot, or a laser.
If you are a new shooter ,I would get use to factory open sights first.
I shot open sights for years, the red dot can be faster for action shooting , But for target bullseye ,It is a toss up.
Lasers are a poor way to learn. O.K. in the movies. or a home shot gun maybe.