When is the best time to get a tattoo?

The summer of my eighteenth year, I was ready to get out of my hometown with my acceptance letter to art school, a pixie haircut, and my first tattoo (a peace sign in the top part of my left ear).  From that moment on, I was ready to start my new adult life in the Bay Area to be a web designer, finally live on my own, and get a few tattoos along the way.

Five years later, I have my second tattoo confirmed and a spreadsheet log of the ones I want next or have thought of over the years.  There are over a dozen ideas and a handful of nixed concepts, but only six so far on the list are definite's and the rest as maybe's.  My goal is a total of at least six pieces by my thirtieth birthday.  Why am I waiting so long for my second if I only have a few years left on my goal deadline?  It's not because I was scared of the pain or the commitment or the taboo of it all.  Money was part of why I'm waiting, but mostly...

I'm a notorious flip-flopper.  A pattern of impulse and immediate regret haunts me through poor choices of either youthful nativity or downright stupidity.  Tattoos are FOREVER - unless they're "removed" or covered with another piece at a cost and time commitment much higher than the original tattoo itself.  I can't let myself flip-flop over ink, so I'm holding off in increasing my ink number until:

1) I've done the research on the piece and its placement.  Avoid unintentional outside meanings that could make things awkward.

2) I have the funds in place.  Going into debt now for ink I can easily get later with saved-up cash doesn't seem logical to me.  I want to have the money ready when my mind and body are also ready.

3) I've had a few years to think it over.  As mentioned, the things I want in life change over time.  I've given myself a three year minimum between the idea blossoming to the full bloom permanent on my skin.

4) I no longer care about the judgments and inconveniences the piece may cause.  Obviously it's gonna hurt and cost money the day of.  After the ink sets and touch-ups are done, I'll be explaining the meaning and the why behind each piece to anyone and everyone who asks, witness the stares and stigmas, and wear clothing and/or makeup to cover them when need be.  The positive thoughts of the piece on my skin needs to outweigh the negative inconveniences of having it.

When is the best time to get a tattoo, really?  These points are helpful to consider, but honesty: do whatever you want with your body once you're age appropriate for ink.  I know mine and my behavior so I'm extensively planning.  I was the kid who wanted to end up a unique adult who makes intentional decisions with the uniqueness.  When is / was your best time?