Indonesian money is quite appealing to collect.
The coins are generally of no interest, although there are some silver and gold commemorative proof coins that are nice, and collectible.
Basically due to high inflation and the poor economy of Indonesia, coins have not played much part in the history of Indonesia.
On the other hand, there is a huge amount of paper money that has been issued, and culturally it is much more significant, given that the smallest note has historically been worth a fraction of a US$, and the largest note is only worth $10, everything is done using big bundles of lovely cash (which changed quite frequently, making a collection of several hundred different notes)
On top of that, you can assemble a collection of most of the money quite cheaply, especially more recent issues (say 1964 and onwards).
To my mind the recent money is not as attractive as the old, but perhaps this is because of inflation.
Probably the two nicest/most popular sets of money are the 1957 animals series and the 1959 flowers and birds series.
The 1959 series (5, 10, 25, 50, 100, 500, 1000) is very affordable, with no real rarities.
http://www.atsnotes.com/catalog/indonesia/indonesia-65.JPG
Only the 500 (market price $60 in UNC) in and 1000 (market price $20-$30 UNC) rupiah notes should cost any more than $5 in UNC condition. Of course if you are willing to buy inferior quality notes you can pick up a full set cheaply.
The 1957 series is much more of a collector's prize. Firstly, collectors love the animal themes on these notes. Secondly, there are some very rare notes in this series.
http://www.atsnotes.com/catalog/indonesia/indonesia-49.JPG
The full set is 5, 10, 25, 50, 100, 500, 1000, and 2500. In addition there was a 5000 rupiah note that was not issued, but is available as a specimen note. For whatever reason, the bank recalled the 10 and 25 rupiah notes after only 3 days. This makes these two notes very rare in issued condition. The price for these two is about $1000 each. The specimens cost less because they tend to be in better condition and also better supply.
For the normal collector, the 5 (gibbon), 50 (crocodile), 100 (squirrel), 500 (tiger), 1000 (elephant) and 2500 (iguana) rupiah notes are therefore available.
Although the 2500 rupiah is given the highest Pick value, the 500 actually seems to be the scarcest.
All the notes sell well above their catalogue value due to wide collector appeal. Market prices are, approximately, 5 rp - $8 UNC, 50 rp $40 UNC, 100 rp $30 UNC, 500 rp $200 UNC, 1000 rp $150, 2500 rp $150 UNC. If you want to assemble a collection for less, than you can get the more expensive notes for about $30 in nice VF condition.
One of the other 1950s series, the 1952 notes are in quite short supply now. These have some nice geometric designs:
http://www.atsnotes.com/catalog/indonesia/indonesia-42.JPG
If you want choice uncirculated notes, you may have to wait a while and pay premium prices.
Most other post 1950 notes are quite cheap, with the highest denominations generally most expensive.
1945-1949 Indonesia money is in a different category, because Indonesia was fighting with the Netherlands, so the quality of these notes is low. This 1945 1 rupiah is one of the more attractive, given this context
http://aes.iupui.edu/rwise/banknotes/indon...piah-1945_f.jpg
There were a total of four series in this period: 1945, 1947 (first issue), 1947 (second issue), and 1948. In addition to these, the Dutch Administration issued 10 and 25 sen notes which continued to be used by Indonesia after independence in 1947:
http://www.atsnotes.com/catalog/indonesia/indonesia-31.JPG
A series of notes was also prepared for 1949 of 'rupiah baru' (new rupiah), but was not issued. These can find a place in Indonesian money collections, but outside of the 100 rp note (supply of these to the market is high - possibly counterfeits), all are very scarce.
Of this period, the 1945 and 1947 money can be obtained with just a little patience. The 1948 money, on the other hand, is very hard to get hold of. The most common note seen is the 400 rupiah, but all notes I have seen sold are counterfeits.
In this period, about 35 districts in Indonesia issued their own designs of emergency money. The quality is generally very low. Supply can also be very poor. Assembling a complete collection is a difficult and time-consuming task, and the money itself does not have the same appeal (some only applied to a few thousand people). There are several hundred different notes to collect, and most collectors will not bother.
In Indonesian money, you can also consider the Netherlands Indies paper money, as this was the predecessor to Indonesia (the last notes are dated 1946). Some of this dates back to the 19th century, but the stuff commonly found on the market usually dates from 1920-1946. There is also Japanese Invasion Money, which apart from a rare unissued 1000rp note, is very cheap indeed due to the massive quantities printed by the Japanese. If you are going to collect this money you will have to contend with the lack of supply (modern Indonesian money is far more plentiful), and also prices which tend to start at a higher level. Due to the passage of time (money destroyed), as well as the action of war (money was destroyed when the Japanese invaded), and the 1950 demonetization of old money, prices for many notes are in the hundreds or even thousands of dollars.
Compared to this, truly expensive Indonesian money is a small percentage of the total population. There are of course a few pricey unissued specimens: 1948 600 rp, 1948 SBNC 'Republik Indonesia' series, 1949 SBNC 'Indonesia Serikat' series, 1957 5000 rp, and 1975 Diponegoro specimens.
But if you stick to issued money, the only $100+ notes (providing you are willing to compromise on condition, going below UNC to say VF) in your collection would be the the 1957 10 and 25 rp. Even the rare pre-1950 notes should be obtainable under $100 if you have patience to seek out and buy at lower grades.
This makes a complete collection of Indonesian money a very realistic proposition (some collectors like to collect serial number variations, e.g., AB 69493 is worth more than A 43544, and if you want to collect these as well you will need more money and patience). I guess there are about 150 notes in total. A complete collection in mostly UNC grades except for the most costly notes will come to somewhere around $1500 (a fair bit of money for sure, but just because there are so many different notes to collect).
