Office space

Hi there, I will be living in Japan for a year and continuing to work in a professional job remotely. I will be near Kashimada Station in Kawasaki, Kanagawa.

I am looking for a way to continue to have a quiet office to work from rather than just using the bedroom at my wife's family's place.

Some of the options I have considered are:
1. Renting a small apartment (these are hard to find and often require a two year contract when I only will be there for a year and there isn't much in the neighbourhood)
2. Renting a portable cabin to plonk on the car parking space at my wife's family home (I haven't been able to find anything suitable in a quick websearch)
4. Getting a room at a guest house (does anyone know any around where I will be staying?)
5. Renting a shared office (can't seem to find anything easily)

I will be arriving at the end of this year so no rush.

If you have had any experience with any of the above or have been in my situation or otherwise have any advice please let me know.

Thanks in advance.

How about public libraries?

I will need to take calls and Skype etc so can't be in a public space.

This article
http://tokyocheapo.com/business/drop-in-coworking-spaces-tokyo/

lists a bunch of shared office spaces in Tokyo.