Are materials and textures included ?

[The 3 Whites]

Are materials and textures included ? Or do i have to buy them extra ?

[ShelLuser]

There's a basic collection of textures and materials, but it's nothing excessive.

Instead of buying stuff I'd consider grabbing Substance Designer too, then you can make your own assets.

[Maxximo]

SP always includes a basic set of materials, both Smart and base ones (Smart ones can recognizes object edges or thickness for stuff like rust or scratched paint).
-You can build your own materials or Smart materials if you own Substance Designer or Sampler.
-You can buy or download for free multiple Assets (from brushes to Smart Materials) from multiple art sites like artstation.
-You can buy Assets as a membership if you have Adobe Cloud Services from the official Substance 3D Assets Store.
-You can download official community Assets for free from the official Substance 3D Community (previously Substance Share).

[Recon]

You can buy some as others mention, but I personally make all of my own in Designer and make all my own brushes in Designer as well.. Alpha maps and so on... Designer is super powerful, and you can build a huge library and if you use Unity or Unreal, you can use procedurally by exposing parameters to use in Painter and inside the game engine....