AFAIK there's actually only one color and you can wrap it. The wrap kits are supposed to be DIY friendly so you can change it yourself when you want a new color.
That sounds a bit like one of Saturn's (1985-2010) original ideas from the 80s. The plastic paneling was easy to take off so that people could DIY change the colors or add their own panels (and Saturn engineers could quickly revise styles). I am not sure very many people ever did, however. Or even if the cars were all that customizable in the end.
This is great if you have a garage to do it in. This is terrible if you’re an apartment dweller and have no workshop space!
The body panels are some sort of composite polycarbonate plastic. They offered a number of colors in the UI for the pre-order system. It basically allows you to configure options that are available and see what it looks like. The wraps are (offered) DIY and they claim it will take two people 14-16 hours. They offer a number of colors that cost $500 right now.
Pretty interesting as far as cars go. I think all of the customization options are really smart, but we will see if that is enough for the average consumer. The number of relatively inexpensive options and ability to customize various details rivals some high end car configuration systems, Porsche is famous for letting you customize every detail.
The way Slate has designed their vehicles, they are making it very easy to change just about anything with the vehicle. I can see this being very popular with young people who cannot afford a lot of car, but still want a highly customized and personalized vehicle that they identify with. We will see if all of the other factors work out in Slate's favor.