Under 18 you can only be pierced with parental consent, and then there is a limitation on what they can do. It is now illegal to tattoo anyone under 18 years, even with parental consent. Problem is good quality tattoo artists abide by the rules, the crap ones don't. If the 18yo is hell bent on getting a tatt, then at least encourage them to go to a quality artist, with a clean studio!
I have lots of mates with tatt's, but i dont have any.
piercings however i have a couple. I had second lot of studs put in my ears at 18.
I had my belly button done when i was 19, it will now not heal up or close over, as i have re-pierced it myself a couple of times, so its permanently open. Even when i went through pregnancy i had no issues with the hole or scaring. My friend was pierced at the same time as me, hers grew out over night about 4 weeks after she was pierced. Basically your body rejects the metal so tries to push it out of your body. If the piercing isn't done deep enough then this happens!.
I had my nose pierced when i was 21. I found it did not want to heal even 4 months later. I ended up taking it out for a job interview, and by the time i got home that afternoon it had partially healed up and i couldn't get it re-pierced so i just never bothered with it.
I had my lip pierced when i was 31. I've had that piercing now for 6 yrs. Again a good quality piercer who knows what their doing, because i have had no gum issues, it sits really good in my mouth/face and i don't even notice im wearing it half the time. Work had no issue with it, and as i work government it's never come up, nor have i been discriminated for having it in future roles i have applied for in the company i work for.
Im with pinkboy.... there is just that bit of pleasure from getting pierced which is why we do it!. Its the same for people getting tattooed aswell, well my friends who are addicted to tattoos anyhow!