28 and I can pass for 18 EASILY.
Here are the things I have faced...
When you are this old, and you look 18, it is MUCH harder to pick up the women around your age. Most of them think... Oh look an 18yr old.
The opposite side of things is that you can pick up much younger women. 17, 18, 19, 20.... I can flirt with all of them, and they will think I am in their age range.
Then you have to figure out what it is you are after. The problem with some guys is that if they are looking for LTR, and want to get married, an 18yr old girl wont do. Then you have to go out and find older ones. If you have a real hard time, you can try the online deal, or just try to go where older girls will hang out.
At the same time too, a girl that looks 23 may only be 18, or heck even 15 if she looks mature. It happens.
You take the hand you are dealt, and do the best you can. If you want the young smokin ones, use your younger looks to your advantage. They will know they are with an older guy, but at the same time you wont look like it, so you wont get stared at all of the time.
If you want the women your age, you have to be out and about where they are. Speak to your friends your age, or co-workers your age to see what you can get.
I'll eventually be out of the job I currently have and will be working for myself. This makes it even 10x as hard because I dont have 30 women or so around me at work, I wont have work friends like older people would, to go out with just to go out, so I have to do it more on my own.
I'll tell you right now it isn't easy, but it will pay off when you get even older.
Some people say... "Even though I get older, high school girls stay the same age". LMAO I always have to laugh at this phrase.