I've moved abroad and come back an embarassing number of times.  Here are a few things I've learned:

1.) living abroad is cheaper than vacationing abroad
When you're local(ish) living is simply less expensive than when you're traveling.  For example, buying a car and selling it a year later ends up costing about what a two-week rental might.

2.) time zones matter more than actual miles
Being awake when your friends and family back home are asleep makes living abroad feel much farther than the actual number of miles you happen to be away.

3.) permits, shmermits
Ignoring the rules makes it harder to come and go, but I've never been hassled about overstaying my visa.  I've heard a lot of people deciding not move somewhere because of the paperwork - to me that's more of a bummer than an afternoon spent pleading ignorance and asking for forgiveness.

4.) sublet/airbnb your place back home
When I moved to Palau, the profit I got from subletting my apartment in New York covered more than the cost of all my rent.  In effect, someone was working crazy-long hours in New York so I could snorkel on Tuesdays on a Pacific island.  I found it ironic. My subletter, probably less so.

5.) ignore the experts  
Because when it comes to the big choices, the big decisions, we're all just beginners.