Using Android Studio with minimum disk space

Update

Note the link for updated requirements. Those listed here are minimal recommendations by Google. More RAM and Disk space have always been better in my experience.

Requirements as of Nov, 2015

Just check out the Android Studio system requirements. You will probably need 4GB RAM and 2GB of disk space to run the Android Studio platform minimally (this is Google's official development platform for Android devices). You can start by downloading the IDE at the developer website and also pickup some samples. So the samples will also take up disk space. Depending on how many versions of Android you intend to support you could be using a lot of disk space for the SDKs and emulators, so you should consider carefully which versions make sense to support.

You might also want to take a spin through the default training site.

2G RAM for AS, 1G RAM for Gradle,

~8G HDD for SDK (incl. NDK),

700M HDD for AS,

~2GB HDD for AS config and caches,

~500M HDD for one project + whatever emulators take

As Eugen Pechanec said as a comment.
I think this is the maximum.