The Australian polymer One Hundred Dollar note is not even 20 years old yet, and all years of issue are still potentially in circulation. There are no rare notes.
One Hundred Dollar notes worth something significantly other than One Hundred Dollars would be those issued by the Reserve Bank of Australia in some form of a folder as a collectible.
Other would include the first and last of a series, such as serials -
AA96 - first (Fraser/Evans)
JK96 - last
(Fraser/Evans)
AA98
- first (MacFarlane/Evans)
CF98
- last
(MacFarlane/Evans)
AA99
- first (MacFarlane/Evans)
JK99
- last
(MacFarlane/Evans)
AA08
- first (Stevens/Henry)
EL08
- last
(Stevens/Henry)
AA10
- first (Stevens/Henry)
EL10
- last
(Stevens/Henry)
Or banknotes with all digits the same, such as 000000 or 555555, etc.
Plastic (polymer)
the plastic Australian notes are made out of polymer
To reduce the chance of counterfeit notes and also to make the notes last longer.
An uncirculated 1988 Australian Bicentennial Ten Dollar note depending on the serial number, could get anything up to $100 AUD. A consecutively numbered group would get significantly more. These notes were issued as a trial for the later release of polymer bank notes. The 1988 notes were not very good and tended to fall apart. They were withdrawn after a short time. A reputable coin dealer will be able to give a more accurate valuation.
You do not specify types, signatories or serial numbers. At worst they are worth $150 each.
Since 1992, Australian notes have been printed on polymer film by Note Printing Australia. This subsidiary of the Reserve Bank of Australia is located in Cragieburn, Melbourne. This same facility also prints New Zealand's bank notes, also on polymer.
An Australian 1988 Bicentennial Ten Dollar polymer note (Johnston/Fraser)(serial AB15), uncirculated and in absolute mint condition could get anything up to $80 AUD. If it has been circulated but still in good condition, it might fetch anything from $15 to $35 AUD. These notes were issued as a trial for the later release of polymer bank notes. The 1988 notes were not very good and tended to fall apart. They were withdrawn after a short time. A reputable coin dealer will be able to give a more accurate valuation.
The new polymer notes are mostly blue but have swirls of yellow and green as well.
The new polymer notes are mostly gold but have a few patches of green and red as well.
Australian Bicentennial Ten Dollar notes with serial number AB26945688 to AB26945693 are from the first release. Uncirculated and in absolute mint condition, they could fetch up to $50 AUD. A consecutive series of notes may fetch more. Circulated, but still in good condition, they might fetch anything from $10 to $20 AUD. This trial issue of polymer notes tended to disintegrate fairly rapidly which is why they were withdrawn from circulation.
There were no Commonwealth of Australia Fifty Dollar notes printed. "Commonwealth of" was dropped from all Australian bank notes after 1972. The first Australian Fifty Dollar note was issued in 1974.
Both old and new Parliament Houses appear on the Australian polymer Five Dollar notes as a symbol of our democratic system of government.