You live in Taiwan? Well... you don't have to worry about someone breaking into your van then.
I thought about it, until I read on forums that these vans get broken into in CA. Criminals scope you out to see when you are away from your van home. They know that there is a high chance you have your laptop, and other valuable items in your van home.
Its not as glorious as you think it is. Everytime you walk into a restaurant, or a shop. Your van home is now vulnerable. What the hell are you gonna do? Take your valuables with you every single time you leave your van? Its just not realistic. What if you wanna jog, do some hiking, or shop for a couple of hours?
Anyways, good luck, I personally would not do it here where I live. Unless I really had no choice.