You are quite right in that PT Central Kuta is NOT a bank. It is however, the most reliable money changer in Bali.
As for storing money, (deposits) I don’t know anyone, or have ever heard of anyone using PT Central Kuta in this manner. In fact, I don’t think they can legally accept deposits, nor issue checking accounts. Do you have an “account” there?
“...but given what happened during Cris-Mo (monetary crisis) i think that caveat might go to most banks as well.”
Here you are referring to the monetary crisis of the late 1990’s. Having no idea where you were during this time, I was here in Bali, and our accounts (Lippo and BCA) were all just fine, although currency exchange rates were “off the charts.” When the IDR hit 17 thousand plus to the US dollar, it was obvious the timing to invest was perfect.
For someone coming to Bali for just six months, the obvious and best advice is to maintain their own accounts from back home and access funds as needed through ATMs.
Perthgirl will also be far better off renting a Kijang or Jimmy while she is here in Bali for six months. The fact is, without a Kitas or higher visa, she couldn’t buy one anyway.