Should I open a
brokerage account for investment?
Can I open
one from overseas?

Stock brokers? Who needs them anymore?
Everything is done online.
If
you think you might want to invest in stocks, mutual
funds and/or bonds, open a brokerage account. Look on
the Internet for a good company. Almost everything can
be done online once you have the account set up.
It
is usually much easier to do it before you go.
Once overseas, it is usually difficult to open a
brokerage account. You will be the square peg that
doesn't fit into the round hole. Many
financial
regulations are based on WHERE YOU LIVE and where the
brokerage company is based. And, while you might not
consider Japan or Korea or Saudi Arabia to be your real
"home" - brokers will not know what to do with you - so
they won't typically do anything.
Online
Get it done
before you go - and sort out any and all the problems of
using the account online. Most brokerages (and
banks and credit card processing companies) have "paperless"
transactions and statements. This is where your
statements are sent to you via e-mail, or you can
download them from the Internet. This avoids having
your family swamped with mail. It also avoids the
problem of having them decide what should be mailed to
you - and what isn't really needed and should just be
thrown in the trash.
Connect with your Bank
Arrange your brokerage account to be interconnected with
your bank. Most brokerage accounts - and most banks -
will allow you to set up back and forth movement of your
funds. Then you can do it all online and you won't
have to make those 3AM phone calls to the brokerage
during their business hours.
Caveat: These are only my opinions, I am not a financial
consultant, but I do have online brokerage and banking
accounts.