This company provide long-term storage (storage space rental) service for various needs. The storage spaces are in different sizes and prices depending on individual needs. They also rent out storage space that is big enough to be used as personal work station too. You can choose to pay the fees monthly, or pay quarterly and yearly fees at discounted rate. They have stores all over the larger Taipei.
The company is call trust-space and this is their website:
The website should contain all the information you need. Unfortunately, it is all in traditonal chinese and they got no english version. But feel free to ask me any question if you need some translation.
I realize many individuals who is related to foreign country one way or another (in general) has such a need.
However, you will need a Taiwan bank account for the company to return the deposit though. (They take deposit for their rental)